What is the best star wars game for pc?

I was in Target the other day, and was going to buy Empire at War, but know nothing about it or any of the star wars games. So I thought before I bought it, I would ask. And also, are they compatible with Vista? I guess I am looking for a game that resembles the characters best...darth vader, luke skywalker etc. and has interesting story lines and not too complicated, if that helps your reply. Thank you very much.