One of my favorite non-Duke war movie has to be The Great Escape. I really like James Gardner as the scrounger. That part just fit him well. Steve McQueen is good too as the cooler king.
My favorites are The Great Escape, Von Ryan's Express, Gettysburg, Gods and Generals, Braveheart, Glory, Stalag 17, We Were Soldiers, and Saving Private Ryan.
Some others I like is The Fighting Sullivan's, Tora, Tora, Tora, Flags of our Fathers, To the Shores of Tripoli, The Guns of Navorone, The Bridge on the River Kwai, and The Patriot (with Mel Gibson).