Leon Kennedy- not afraid to suplex zombies, has been in survival situations since forever
Bill Murray- Funny keeps group entertained, smart enough to find ways to safely salvage and live comfortably
Optimus Prime- No such thing as machine zombies and always in support of human race
Sinestro- Ring powered by fear? He'd be the most powerful guy on earth in this situation, plus the constructs would come in handy
Kim Possible- anything is possible for her, she always gets out of bad situations safely with no kind of casualties at all and she's 18 so... we need to repopulate eventually, Bill is too old, Optimus is a robot, Sinestro is a diff species and Leon is too bad ass.
Silver surfer- To instantly kill any and all zombies we may come across and also able to make the things we need.
Big Boss- To give us the best tactical advice on how to survive. With the boss teaching me, I may just make it out of this thing alive...
Scribblenaut- To supply food, medicine, guns and ammo as they are needed.
Proffesor Xavier- Always useful to have another telepath who could find out peoples true motives. As we come along survivors, he could mentally make survivors do what needs to be done, and he is wise enough and respectful enough not to abuse that power.
Dante (DMC3 version) - Comic relief and is more than able to hold his own.