Most of my faves have been listed already, but I'll do it again:
Patton
Black Hawk Down
We Were Soldiers (Moore was an LTC, not a COL, commanding a battalion, not a brigade) [Speaking of nitpicking...]
Memphis Belle--"Somebody's guts are all over the nose!"
The Longest Day
Tora! Tora! Tora!--Fantastic film.
Das Boot--I've been on the Das Boot set stuff at the Bayernische Filmwerken in Munich. Great fun. Remains one of my most favorite of war movies.
Lawrence of Arabia
The Battle of Algiers
Platoon
Apocalypse Now
Full Metal Jacket
Bridge on the River Kwai
Master and Commander
Glory
A Bridge Too Far
War movies that I'm less fond of:
Pearl Harbor--It was a travesty how Pearl Harbor tried to glom on the key parts of Tora! Tora! Tora! to the drivel that was at the heart of Pearl Harbor. Also modern guided missile destroyers and cruisers make very poor WWII destroyer/cruiser stand ins. It's like they didn't even try...though the trailers with just the music and the planes were amazing.
The Thin Red Line--My film major roommate my senior year loves it, but to me it was less than compelling.
The Great Raid--Decent, but it suffers from being about an event that was too small to make a good two hour movie. This is not to take anything away from those who participated in the actual events, but not enough on its own for a good flick.
Midway--Suffers from the Pearl Harbor syndrome, trying to superimpose human relationships on events that transcend them. I wouldn't be ashamed to own this one, however.
U-571
Windtalkers--I kinda liked it first time round, but the shine quickly wore off. Also grainy shots of battleships really did not work well with the rest of the film. And the frag grenades with the explosive and fiery effect of incendiary bombs...geesh.
I'm told that Harrison Ford is doing a movie based on Bing West's
No True Glory about the Marine's battle in Fallujah, Nov 2004, which I am most interested to see.