What do you guys think about the shotgun? Fire?

I had an argument with a friend about methods of dealing with zombies and I think he was under the impression that because he's a guy he's right and I'm wrong. I'm copying the text of the argument here as it was done in a chat, and you guys can tell me what you think, I will warn that I got very angry near the end because he wasn't listening to me. And warning, it's kinda long, I cleaned it up the best I could and removed the non-zombie related parts of the argument, but yeah.

Him: According to Left 4 Dead, it's good for one person to have a scoped rifle for long range attack, two people to have a assault rifle for medium range attack and for the last person to have a semi-automatic shotgun for when they get really close. Pipe bombs and Molotov's are great ways to temporarily stop hordes of zombies which buys you crucial seconds to reload your guns and apply any health kits. Make your way to the closest known rescue site, but don't move too fast or too slow. By moving too fast, your group can separate with the team members trailing behind a leader leaving each individual exposed. By moving too slow your group can get constantly hit by hordes of zombies and you'll run out of ammunition and get your guts ripped out. Make good use of any propane tanks, gasoline containers and hydrogen tanks you come across as either explosives by shooting them or creating a barrier by causing a fire. Once you get to the rescue center and you call for help by radio, prepare for the onslaught after onslaught of zombies that come for you. Try to stick together, if one of your teammates gets dragged off and it looks hopeless for him, don't try to save him. Otherwise you risk death yourself. Conserve ammunition and make your way to the helicopter/boat/airplane/armored vehicle when it arrives. Run if you have to. At this point, it's everyone for themselves.
In Left 4 Dead, there are zombies EVERYWHERE. Half of the game takes place in reaaalllyyy remote places and there are STILL TONS of zombies. And EVERYONE knows that Left 4 Dead is a true zombie simulator. Going to a remote location won't do anything. So be prepared. You're not safe ....... anywhere....
Lol one of the levels is like farm land yet on the harder levels you kill like an entire city's worth of zombies.
The game is a lot of fun to play with people you know, keeping each other alive. It's available on both the Xbox 360 and PC. Up to four people can play at a time and it's essentially a zombie survival game. Maybe I'll put up a video on here.

Me:FIRE IS BAD!!!! even in Left 4 Dead the zombies didn't lie down and burn to death they became WALKING FIRE TRAPS!!! Lighting up a zombie is really really really really stupid. they will catch the other zombies and everything near them on fire just by wandering around, and wouldn't you feel silly getting killed by the fire YOU started.
Remote is as far as you can get, but still livable. You'll have to be able to grow food, since you can't know how long the zombies will last.
Sniper Rifles are usually just a rifle with a scope. So, yea.
Shotgun would be COMPLETELY useless because IT TAKES A HEAD SHOT to kill a zombie. wasted weight to carry.
Left 4 Dead hinges on the idea that zombies are not contagious. That's unlikely. med kits would only help in non zombie related injuries. other than that, you're screwed.
And in reality, there won't be propane tanks and other such explosives just lying around. ever.
and even if there were, the head thing still applies. if it damages the zombies, yay, but it won't stop them. that's why the machete is the most essential, because it's long and easy to use and doesn't need to be reloaded. rifle would be for back up.
I will agree that stopping to try and kill each zombie is a good way to die, by staying still, you're letting them box you in.
Another good reason to go to a remote place, no other living people who might shoot you thinking you're a zombie. that would be another really dumb way to die.
Left 4 Dead is wrong about remote places. zombies would only be where people are. it takes a dead person to make a zombie, so logically there wouldn't be zombies were there aren't people. and zombies aren't smart, they stay near where they die to hunt, and don't tend to travel long distances. zombies aren't going to travel hundreds of miles to eat you when there's food locally. it's just logic. there's always a chance, but it's pretty damn ... well remote.
Him: Pshh, the fire worked well in slowing them down which buys time to drive many bullets into them in Left 4 Dead. As long as I didn't blow up any gasoline canisters real close to me or throw a molotov on myself, I was fine. And fire is oh so crucial in quickly killing tanks. Takes SOOO much to friggen kill them with bullets on Advanced. I don't even wanna know how hard they are to kill on expert.
But on a more realistic viewpoint.
A Shotgun would be VERY useful in disabling many zombies at one time. They might not die from the initial shot, but they'll be much less mobile and less able to reach you if even at all. You can worry about finishing them off later when time permits. It's not wasted weight at all. Trying to headshot every single zombie that comes by only works if there isn't a swarm of them. And even then, good luck trying to headshot anything that moves with a single shot without a scope and being prone. It takes quite a bit of skill to have that type of marksmanship. Skill that the vast majority of people don't have.
In reality, if you're in the middle of no where, then there won't be any propane tanks or anything. But it doesn't matter because propane tanks don't explode when shot at in reality anyway. I don't see why gasoline canisters would explode either unless you used a incendiary round.
I'd really hate to use a machete because that means the zombies are right up to the person. If it's not 1 vs 1, you're screwed because the machete is more of a strength than speed based weapon which means you're going to have open sides for other zombies to attack from. Even if you manage to cover all of your sides, you can change the magazine in a assault rifle in all of a second while you're going to get tired quite quickly with a machete unless the person has quite the endurance which again, most people don't have. If you screw up with the machete, there is no time for a rifle backup (why would you use a rifle anyway? A rifle is only good for field use. Sub machineguns and pistols are much more effective for close quarter/urban combat) because it'll already be on you and tearing you apart. I'm not quite so sure what you mean by a machete being easy to use either. Have you used a machete before? You kinda have to know what you're doing when swinging it, otherwise the machete is liable to get stuck in whatever you're trying to cut and/or your hand is going to really hurt. Similar in the sense of using a axe. I doubt most people would know how to use a machete.
In a realistic situation, I'd say people would be best off with a shotgun or semi-automatic rifle. The rifle provides accuracy for the people who somewhat know how to handle guns and the spread of the shotgun pellets compensates for the lack of aiming skills for the others. Both being semi-automatic weapons also keeps itchy trigger finger people from wasting too much ammunition as well. Pistols could be used but honestly the short barrel and lack of a stock makes them hard to fire accurately without a lot of practice.
You can argue that a machete will last longer because it doesn't need to be loaded with limited ammunition, but blades quickly become dull with use and if you have no way to sharpen the blade well, the machete will be just as useless as a unloaded gun.
Me: THE WORLD IS NOT A VIDEO GAME!!!!
enough said.
and R*****, just because you've played a zombie game, doesn't mean you're an expert. not to say I am in anyway, but I've spent the last five years obsessing over zombies, so I think I've given it more thought. try reading The Zombie Survival Guide, which does a good job of discussing the different types of zombies as well as how to deal with them.
and the head shot still stands. your argument hinges on zombies acting like live people. unless you have buckshot for your shotgun, which is expensive and well controlled, you have to be within like a yard to do any damage and then they still won't stop BECAUSE THEY'RE ZOMBIES! they never stop until the head is removed. so you knock one over, it'll get up. shotguns are a death trap. and again, you didn't disprove my point about fire. you said "it'll slow them down." why? does fire weigh something? they are dead they feel nothing and they want your flesh. they won't stop just for a little fire. duh.
and in the end, you aren't supposed to be fighting them you're running, the machete and rifle are for situations where you can't just run. they're zombies, they aren't very fast. you can almost out walk them. just don't get cornered.
just because it works in Left 4 Dead, doesn't mean anything. I've played it too. it's nothing like real zombies, fun, but nothing like them.
Him: The fire part I was just talking about Left 4 Dead, I wasn't talking about that realistically.
The rest I'm not talking with a zombie game in mind at all, I'm talking in mind with real live physics, the composition of living (used to be living) tissues and how firearms work. No matter what you're up against, real live science comes into play.
Shotgun shells are not going to just make zombies "fall over." They can be used to blow off actual limbs, especially if their flesh is already decomposing. They can still be trying to come after you but they'll be moving MUCH slower if they are missing limbs. that's the idea behind the shotgun. If there are a bunch of them, as you mentioned "situations where you can't just run" A shotgun blast at the height of the average human head from several meters away will kill a good number of zombies with one shot (if they're bunched together and surrounding you which I'm assuming is what you mean by being trapped). You also have to remember that bullets/pellets don't always stop after hitting something once. It's likely the pellets will exit initial wounds and continue to kill or disable even more zombies. All with just one shotgun shell. THEY ARE NOT DEATH TRAPS. Unless you've got some REALLY lame shotgun shells, they can be very useful. NONE of this is taken from a game, this is how shotguns and reality works! At close range, a shotgun is MUCH more effective at killing a zombie than a rifle.
Like I mentioned before, in a "situation where you can't just run" a machete is what will be your death. You're better off firing a shotgun and reloading while another person fires a weapon than trying to cut through zombies all day. And if you're alone, you're screwed anyway. If you feel like you can realistically wack at things with a machete all day AND stay at a safe distance so nothing can grab at you AND be able to travel large distances as quickly as possible to get to a safe area then be my guest. But cut out the wacking and you'll have a lot more energy to travel farther and make better time and progress rather than finding yourself dead tired and still in zombie land.
And again, this is even if you know how to use a machete. If you don't then you're going to get tired and be sore MUCH faster.
I don't see how I'm trying to kill them all, I'm just trying to point out that a shotgun is a much more effective weapon than a machete! That is my main argument. I don't know why you like a machete so much but if you have a shotgun with a bunch of shells, I don't see how a machete is better in anyway.
Anyhow, whatever.

Me: no it won't no it won't god I am so sick of this I'm actually getting angry. Talk at the party. Your physics are flawed. Have you ever actually shot a shot gun? cause they don't do much damage. that is physics. and I can't get into the rest of this because I'm so so so so sick of it that I'm shaking at this point. You keep acting as if you'll be fighting hundreds of zombies. you won't you'll be running if you're smart. they shuffle for god sakes. you'll kill like ten max, and only because you couldn't get around them.
HEAD GOD DAMMIT HEAD! you ignore the head rule. so shut up till you figure that out.
SHOT GUNS DON'T MAKE YOU EXPLODE! THEY SHOOT TINY ASS PELLETS AND THEY ARE ONLY FATAL BECAUSE THEY HIT ARTERIES AND ORGANS, WHICH ZOMBIES DON'T CARE ABOUT. DUH. YOU WOULD NEED BUCK SHOT TO DO ANYTHING THAT WOULD EVEN REMOTELY RESEMBLE WHAT THEY DO IN VIDEO GAMES AND EVEN THEN THEY ARE STILL BLOWING HOLES. YOU NEED TO DESTROY THE HEAD AND A RIFLE OR A MACHETE WOULD STILL BE THE EASIEST. GOOGLE A SHOTGUN AND READ UP BEFORE YOU SAY ONE MORE DAMN THING ABOUT THEM. NOT TO MENTION YOU CAN'T STOCKPILE AMMO, YOU'LL HAVE THE COPS AT YOUR DOOR. UGH.
Him: lol yeah. Even after thoroughly researching shotguns, I still don't see what's so bad about them against zombies in close range.

Which brings up the question, just how badly do you have to damage a zombie's brain anyway before it "dies"?