Here's my list of potential films:

A) Alien (1979)
Amadeus (1984)

B) Bicycle Thieves (1948)
Blade Runner (1982)
Black Swan (2010)

C) Casablanca (1942)
D) Das Boot (1981)
E) Elephant Man, The (1980)
F) Fargo (1996)
G) Godfather, The (1972)
Godfather Part II, The (1974)
Green Mile, The (1999)

H) Heat (1995)
High Noon (1952)
Highlander (1986)

I) It's a Wonderful Life (1946)
Island of Dr. Moreau, The (1996)

J) Journey to the Center of the Earth (1959)
K) Kick-Ass (2010)
L) Lawrence of Arabia (1962)
Léon: The Professional (1994)

M) Memento (2000)
M (1931)
Metropolis (1927)
Men in Black III (2012)

N) Nosferatu (1922)
O) One Flew Over the Cuckoo's Nest (1975)
P) Pan's Labyrinth (2006)
Q) Quiet American, The (2002)
R) Reservoir Dogs (1992)
Requiem for a Dream (2000)

S) Shawshank Redemption, The (1994)
Schindler's List (1993)

T) Taxi Driver (1976)
Trainspotting (1996)

U) Usual Suspects, The (1995)
V) Vampyr (1932)
W) Wild Strawberries (1957)
X) X-Men Origins: Wolverine (2009)
Y) Yellowbeard (1983)
Z) Zorro Rides Again (1937)
Zack and Miri Make a Porno (2008)
Zoom (2006)
Zambezia (2012)