For anyone who does want to actually partake in any zombie discussion, the only type of zombie that's really considered as 'canon' for this zombie movement is the Dawn of the Dead/ Romero type. They're described at great length in
Max Brooks' Zombie Survival Guide, and he was a Zombie Consultant for the Dawn of the Dead remake a couple years back.
Other types of zombies - Resident Evil, Day of the Dead, and 28 Days Later (though that was Rage, not zombification) - are not generally accepted for argument.
In short: Terribly slow, terribly stupid, terribly stubborn. Not much else.