I'm a fan of George Romero's original Dead Trilogy(Night, Dawn, Day - His last two films were okay but not up to par with the original trilogy). As for most other horror films…I'm not really into them. Romero is one of the few that can actually scare me because his films are about the TRUE horror - humans.
Yeah, his films are about zombies in a sense, but that's not the frightening thing about them, imo. The frightening thing is that if you watch his films, it is ALWAYS the humans that screw themselves over in desperate situations. The zombies don't mean to be what they are….they just are. We could easily fix the problem if we all worked together, but we just can't do that. In the end, we will cause our own demise. That's the scary thing to me…