It was a pretty decent list overall. As others on this thread have been saying, there were a few films that should have made the list and a few that shouldn't have, but all lists are subjective. The only list that will ever be perfect in one's eyes is his or her own list.
I never found Cujo very scary myself, so there is no way I would put it up there. Single White Female and The Game are also nothing truly special but whatever. It was too bad that Wes Craven's New Nightmare didn't make it because it is a personal favorite of mine. I also like Frailty, The Cell, Evil Dead II, Army Of Darkness, Hellbound: Hlellraiser II, The Phantom Of The Opera (Robert Englund version), and Dark City. Those are all films that I think should have made the list. Like I said before, though, no list is perfect. Besides, it was a fun thing to watch with friends for Halloween. We had some interesting discussions about the films. I hope they keep playing it, so I can tape it and always have it for future Halloweens!