I didn't try the duel's when i had rented it, but the wii does a half decent job of lightsabering, but it's not perfect, and the game is more focused on force use than lightsabers, one of the biggest complaints from people i think. It's pretty decent though. You bascially can do left/right to start the attack and then left/right/up/down for the final combo swing. Might be a little diff in the duel mode, but again, didn't try that part. You can also throw in force moves after the first 2 swings to do different stuff.
John