Cool Hand Luke
Bridge on the River Kwai
Schindler’s List (does this count?)
Shawshank Redemption
Take the Money and Run
After some of those mentioned above, I’d go for Birdman of Alcatraz, and one of Sean Penn’s best, Dead Man Walking
The aforementioned “Animal Factory” was directed by Steve Buschemi and written by Eddie Bunker (Mr. Blue in “Reservoir Dogs”) about his days in prison. It’s a pretty good movie, although inconsistent.
I gotta go with “The Great Escape” on this one. The other day, I started whistling and it lasted for an hour before I realized I was whistling “The Great Escape” theme. That’s how great the movie is. Hehehe.
–greenphan
I’m going to have to go with Papillon. Not just a great prison movie, a great movie period. Honorable mentions to The Shawshank Redemption, The Green Mile and Cool Hand Luke too.
I’ve liked a couple of the ones that have already been mentioned (The Green Mile, The Shawshank Redemption), but several obscure films also come to mind:
Greenfingers - An inmate with a green thumb enters a national gardening competition. (Based on a true story.)
Lucky Break - Inmates concoct a scheme to escape by staging a musical.
Stranger Inside - A mother/daughter reunion in prison.
Check out SHORT EYES.
IMDB’s tagline: “A child molestor sent to prison finds that criminals exact harsher justice than society.”
http://us.imdb.com/title/tt0076706/combined
In a word: Potent.
The Linda Blair flick Chained Heat was always a favorite of mine.
let me plug “reform school girls”, for so many things but chiefely Wendy O Williams (late and lamented) and a truly archetypical bull dagger matron.
Stir Crazy
It’s one of my favorites too (and one of only 2 movies to bring a tear to my eye), but unfortunately didn’t qualify as a sizeable portion of the movie didn’t take place in a prison. Your other picks are good as well.
It looks like the top contenders so far are Cool Hand Luke, Shawshank Redemption, and The Green Mile.
Good call there, danceswithcats – I also think that Sean Penn’s best work was Dead Man Walking. His performance just before his execution kinda shook me up.
Looking over some of the posts I see I need to go rent some movies.
Surprise, surprise… The Shawhank Redemption along with The Green Mile and American History X.
Oh, and throw in the Hurricane.
How can nobody have mentioned I Am A Fugitive From A Chain Gang? As the allmovie.com critic writes, it makes Cool Hand Luke look like a picnic in the country.
Oh, it was definitely the first prison movie I ever saw, Peter Pan. I remember it well…I was doing 3 to 5 in Folsom for passing bad Czechs and after the movie Fat Andy and I went for a stroll behind the grease pit…
sigh.
What?
My vote would be Murder In The First with Christian Slater and Kevin Bacon
I did enjoy the scene in bad Boys where Penn loaded the pillowcase with coke cans and took care of business.
Other than that it would have to be Shawshank, Cool Hand Luke, The Great Escape and Papillon. Maybe Alcatrez as a distant fifth.
No one’s mentioned Tango & Cash yet? Come on. 
I’d go with The Great Escape, although for some reason the last shot of The Shawshank Redemption kinda gets to me.
Shawshank is one of the best movies ever, regardless of its prison setting. Longest Yard also gets a vote for me.
The Defiant Ones
The Executioner’s Song
Prison Heat, starring the amazing Lori Jo Hendrix. Her body alone is reason for a sequel.
I’ll second Birdman of Alcatraz. In fact, I originally didn’t see Shawshank Redemption because I thought it was going to be a cheap rip-off of it. I was wrong, they are both great movies.
I also liked American Me