Robomatic, that was "The Long and the Short and the Tall," also known as "Jungle Fighters' in the U.S.

That Stallone POW movie was called "Victory" in the U.S. I heard it was so bad I never bothered to see it.

In fact, the songs in "Oh What a Lovely War" are indeed from WWI and not "modern." The sense of irony and ridiculousness in the ditties of British soldiers was famous.

"Stalingrad" is rentable. Technically it's pretty good, but it has plenty of cliches as well. "Enemy at the Gates" is surprisingly good, and a much more interesting film, IMO.