Well, das Boot came out well before we were all sick of the WWII European front. I think it's a 1981 movie. It's by Wolfgang Peterson, I believe (Air Force One and In the Line of Fire). Except it's better than those.
And definitely watch it with subtitles. The English dubbing turns it from drama to comedy bronze. The remastered DVD edition also has incredibly badass 5.1 digital sound. You'll think your living room is about to implode from water pressure.
Watch this film, and you'll realize Crimson Tide and U-571 were ripoffs.