Glad to see some love for Let the Right One In. It's not completely horror, I agree, but it's got some pretty horrific scenes in it. And if you really look at the overall picture, and what happens to Oskar while he's with Eli, his fate is actually quite tragic and, well, horrific.
Martyrs was an incredibly graphic and bloody film, by far the most disturbing film I've ever seen. But the concept behind it is actually amazing and imaginative.
I'm a huge fan of horror sagas like Elm Street, Halloween, Hellraiser, Evil Dead, Alien, and Saw (and Friday the 13th to a lesser extent). Saw is an incredibly underrated horror series and much of the hate it gets is pretty unjustified. Most of the critics who bash it don't even seem to understand what the hell is going on.
Giallo films are usually a hit or miss for me, but when they're a hit, they're amazing. Mario Bava's giallo work is mostly pretty solid--Blood and Black Lace, Black Sabbath, Tenebre, Kill, Baby, Kill. He's my favorite Italian horror director. I don't consider Dario Argento to be quit up to par with Bava, but he has quite a few classics as well--Suspiria, Deep Red, Opera.
Still, I stand by my top 10 list