Okay, I really doubt the Romero zombies would ever become read. The dead being reanimated? I'm pretty sure dead cells stay dead. And how would the virus make it so that you have to shoot them in the head. It's impossible to create such an organ than can control the WHOLE body in such a way that it works almost perfectly, and in some cases, better than our. Our body NEEDS almost all the vital organs (thus the word VITAL). Even cells need the organelles to survive, not just the nucleus.
If any zombie would be created, it would most likely be a mix between 28 days later and an original zombie.
It probably would be along the lines of a human with extremely violent outbursts. It would die the same as humans. If it gets shot in the torso, it'll probably die. Extremely contagious, though. It'll probably profusely bleed, and the blood is where the virus would be. I doubt the saliva would be a big issue. Though, I don't know if it would be very coordinated. Since the mind is altered, I can't tell if it could think. All it would think about is "YOU MUST DIE!" like a bull to a matador.
This is all coming from a 7th grader, just to let you know in case I have this all wrong.