[b]All[/b] corpses will turn into zombies given the proper circumstances.
However, there is a very important fact that is overlooked by most here. A "zombie-bite" zombie is much more dangeroous than a "dead-and-buried" zombie. This is because the zombie-bite zombie has not decayed and is in a much better physical condition than, say, a zombie that has been interred for six months or better.
Both are determined and sluggish, but the zombie-bite zombie is a much more dangerous adversary. If you come across a human who is pending transformation into a zombie, your best bet is just to decapitate them on the spot. The transformation process is very painful and not-to-mention, very dangerous for you.
If you have any more questions regarding zombie infestation, please feel free to ask.
J. Reno
Zombie Exterminator