I'm a big war movie fan, so here's the first batch of recommendations, just off the top of my head:
Cross of Iron
Kelly's Heroes
The Dirty Dozen
The Guns of Navarone
Force 10 From Navarone
Saving Private Ryan
Schlindler's List
The Great Escape
The Bridge on the River Kwai
Patton
Black Book
Soldier of Orange
Das Boot
The Pianist
The Longest Day
A Bridge Too Far
Where Eagles Dare
The Hill
Stalag 17
Enemy at the Gates
A Midnight Clear
Tora! Tora! Tora!
The Thin Red Line
The Big Red One
Catch 22
Von Ryans Express
Stalingrad
They Were Expendable
The Dam Busters
Memphis Belle
Run Silent, Run Deep
Downfall
Attack Force Z
The Sands of Iwo Jima
Flags of our Fathers
Letters from Iwo Jima
Hell in the Pacific
Hell is for Heroes
The Desert Fox
The Great Raid
Hart's War
Blood Oath (aka Prisoner of the Sun)
Never So Few
The Battle of the Bulge
The Battle of Britain
The Eagle Has Landed
The Heroes of Telemark
Castle Keep
1941
The Bunker
Zone Troopers
Though I'm sure I've missed a few classics, I think that'll do for starters...
