Oh, and I am not sure how you define a franchise, but if it's a "universe" (like anything Mario is a franchise), then I would have to say Star Wars is way up there.
X-Wing stuff, Knights of the old Republic, the RTS they had was good, Jedi Knight series... Lego Star Wars... they have had a lot of great games (and that's uncommon for a movie license)
Edit. Forgot about Rough Squadron, and the Pod Racer games.







