Some Must-See English Movies

Citizen Kane (1941)
The Sound of Music

Stanley Kubrick's:
Dr. Strangelove
A Clockwork Orange
The Shining
2001: A Space Odyssey
Full Metal Jacket

bourne identity and supremacy (i thought the assassin in bourne supremacy.... forgot his name, was 'solidddd'- great fight sequences and car chases, once again)

Quentin Tarantino's:
Reservoir Dogs
Pulp Fiction
Kill Bill vol. 1

Raising Arizona (By Farelly Brothers)

Jack Black's comedies- Shallow Hal, School of Rock; this guy is an awesome comedian, and a great singer, I found out (school of rock)

Dr. No (James Bond)
Donnie Darko
Spartacus
Arthur (the one with Clive Owen; awesome script, since it relates of Arthur's legend as markedly different from the popular myth... that he served the roman army and gained only 'minor victories'; didn't show merlin as a pure wizard, but proficient in some dark magical powers, and Arthur's archery-capable army really came from his love's armies. etc, etc.)
Troy
Cold Mountain

Invincible Sci-Fis:
The Matrix (part 1 only)
Terminator 1-3
Alien (part 1 only)
2001: A Space Odyssey
E.T. (Although I only liked Drew Barrymore's part in it)
A. I.

But then, my list is dynamic... it changes constantly... and there are innumerable more that are really worth watching...