In no particular order:
The Shawshank Redemption
Pulp Fiction
Fight Club
V for Vendetta
The Game (not trolling)
The Godfather (parts I and II)
Batman Begins & The Dark Knight
Inception
The Matrix (forget the sequels exist, do not watch them)
Red Dragon & The Silence of the Lambs
Indiana Jones: Raiders of the Lost Ark
Se7en
The Usual Suspects
Memento
The Prestige
American History X
Forrest Gump
Full Metal Jacket
The Princess Bride
Star Wars Saga
Inglorious Basterds
Gran Torino
Hotel Rwanda
No Country for Old Men
The Sixth Sense
The Count of Monte Cristo (one of my all-time favorites)
Good Will Hunting
A Beautiful Mind
Gladiator
Shutter Island
Jaws
Terminator 1 & 2 (forget all of the others)
The Professional
Monty Python and the Holy Grail
Back to the Future trilogy
A Clockwork Orange
Saving Private Ryan
Lord of the Rings trilogy
Alien, Aliens, and Prometheus (at all costs do not watch Alien vs. Predator)
Predator
The King's Speech
Rear Window (Hitchcock classic, one of my favorites. Don't be put off by its age.)
One Flew over the Cuckoo's Nest
American Gangster
Inside Man
Ides of March
The Ghost Writer
Also, if you're looking to get into some TV series:
Dexter
Breaking Bad
Fringe
Homeland
White Collar
Person of Interest