There are a few games I enjoyed from the Star Wars collection.
Knights of the Old Republic certainly was an amazingly, awesome game. It has gotten my interested in RPGs more than I was interested in them before. And it makes one helluva fun game to play.
I just finished playin' Republic Commando, which I enjoyed. May try it for Xbox, too. I would definitely like to see a sequel/prequel for it.
Empire at War was okay. Though, I haven't played it since it was released a year or so ago. So maybe I need to start playing it again.
Battlefront was fun when a first started playing it when Revenge of the Sith was just released in theatres almost two years ago. I still play it online. I also might have to play Battlefront II again once I get my 360 since it is compatible on the 360, and download that little expansion thing and try it out.
Though, overall, I'd have to give it to Knights of the Old Republic.