Well pvt. I think the word is "sympathetic", in the sense you share their feelings. You share . . . you care. So many of modern characters would be the ones you would maneuver away from at a party for fear of having to listen to them all night. Why spend good money to hang with a bunch of them for two hours? I think such movies entice us to loathe a character so we can rejoice in his (usually) death. I've often thought: "Oh, will somebody shoot this A-hole!!??". They're often not a real bad-guy, just stupid or annoying; so it's like rooting for the death of regular person. Kind of insidious and mean-spirited, but it gets a cheer or a laugh.
That's not my point though. If this were a slasher flick like Jason or Halloween or nightmare on Elmstreet then yeah, you're rooting for the villian and want the characters to die. But this is a supposed horror movie. If the characters were ones you cared about that would make the horror more real.