If you're going to have all the dialogue in French and/or German, the title should be in that language too - I suggest French, as they'll be the heroes. I don't think you should just use "La Guerre des Etoiles", though, the title should somehow reflect the WWIII idea.
If it's meant to be like an old French war movie, you should have French subtitles for the German and English dialogue in the 2.35:1 area (over the picture) and English subs outside the 2.35:1 area (in the black "letterbox" area) - but you might want to keep these inside 1.78:1 for those with 16:9 TV sets.
The crawl should also be in French with English subs.