Here is a movie scene that imo is the best or at the very least one of the best movie scenes in movie history.
This is an old Quinten flick made in 1984 called True Romance. This scene is between two legendary actors: Dennis Hopper and Christopher Walken. If you have never seen this movie I highly recommend watching the whole flick. It has some other seens that I think are some of the best as well. Like the scene with Christian Slater and the pimp and the one with James Gandolfini (Tony from Sopranos) and Patricia Arquette is down right brutal. The scene where Brad Smith is a stoner is just plain out hilarious.
YouTube - True Romance - Sicilian Talk