My crew opts for upbeat jazz. "Juin" is a favorite. Some others are "Hallo Fraulein" and just about anyting from Edith Piaf, "The little sparrow". I was listening to "Mariandl", which is really catchy (you'll find yourself humming the tune out of game if you listen to it), but read somewhere that this song was sung by Petula Clark (of "Downtown" fame), so it's not WWII vintage. If anyone knows differently, please advise.
Oh, and by the way, in the "Ultimate Gramophone Pack - 150+ Tunes", "Under the Sea" is not sung by Frank Sinatra - that's Bobby Darin.