Great topic. I love horror movies but don't know many of them beyond zombie ones (which really aren't even horror movies after a certain point *cough* Resident Evil *cough*).
I'm a huge fan of 28 Days Later.
Resident evil was good at first but then they like totally went a different path with it and I stopped liking it.
The second one was godawful. CGI wasn't advanced enough at the time of that movie so the main mutant looked like a computer animated turd, really.
Third one wasn't so bad if you could get over the whole "Alice has superpowers now" thing.
But yeah, the first one was good. It was probably the only one where you could point out the obvious video game link. Don't even get me started on Resident Evil: Afterlife. Great eye candy, but that's about it. Not any horror to speak of.