The Blair Witch Project is scary o.O. But The Blair Witch Project 2 isnt ;( :p.
I also like The Ring and The Ring 2. Screams, I Know What You Did in Last Summer and I Still Know What You Did In Last Summer were good too but maybe a little teenage. Older but pretty good scary movies are for example Halloween and Friday The13. I found a movie called Jerusalem's Lot at our local library. It was quite scary too.
If you need some parodies which based on scary movies, watch some Scary Movies. Them are funny :D.