When Harry Met Sally (For me, every scene is perfect)
Silence of the Lambs (when an older-than-middle-age villain is behind bars, and is still frightening to the viewer, and he's, in a way, the hero of the movie, it's hard to beat a film like this for it's genre)
Godfather 1&2 (I still watch these as 1 long film)
Fargo (black comedy at it's finest)
Star Wars (The attention to detail and so many aspects of how revolutionary the filmmaking was for its time...still holds up)