I know Adam and Sam did a horror movie marathon early on but only two of those movies were actually scary. I think Texas Chainsaw Massacre and Halloween count. The rest of the movies are physical comedies that are just gory. I know they are classics but still you could have done a lot better. I think they even admitted this. Here are the movies they need to see:
Audition - 1999
Ju-On
Ringu
Saw - 2004
Hostel - 2006 - 70% on rotten tomatoes
The Descent - 2006 - 83% on Rotten Tomatoes/70 on Meta Critic