1) Marc would obviously get killed first because he's a minority. Everybody knows that white people survive at least the first thirty minutes, but others aren't so lucky. And please, he's even an indian! There's no reason to keep him around once he's warned us about whatever curse or legend we're going to blatently ignore (until it eats us).
2) I'd go second because it's pointless for a woman to stick around more than two or three scenes with no potential love interest. Also I'm the dark-haired, smart, scientific chick, nobody ever wants to see them last the full 90 minutes (apparently).
3) My roommate's boyfriend would go third. he's good comic relief and you'd have to feel bad for him, but he's not tall enough to be the hero.
4) Four: the dog. he'd be protecting my roommate (not us, trust me) and animal sacrifices really give people an emotional attachment to the plot.
5) Not sure if my roommate would survive this or it'd be all-out slaughter, but I'm guessing she'd survive because blood looks very dramatic on blonde hair. she'd have to do the final desperate stumble outside to see the army finally show up to (not) save us.
So that's why Marc and I stayed upstairs and let her go down and tell us it was just her intercom thing going nuts again. sure...