Singing in the Rain
The Princess Bride - "As you wiiiiiiiiiiiiiiiish." If ever there was a timeless story, it's this one. This film has something for everyone. Stellar performances by Cary Elwes, Mandy Patinkin (for whom my love knows no bounds), Robin Wright, Billy Crystal, et. al. This is definitely one to own.
Cary Elwes and Robin Wright - Princess Bride
Eternal Sunshine of the Spotless Mind, Michel Gondry