RE: Scaryest movie
If no one has ever seen "IN THE MOUTH OF MADNESS" you should definetly rent it. It never got a lot of press but it is a great movie. Charlton Heston was in it as well. I wouldn't say that it is "make you jump out of your seat scary", more like it gives you the chills all over your body through out the movie scary.
Amityville horror was pretty good. The book was even scary.
Final destination 1 & 2 were pretty good.