After you swing across the pit by hooking onto the generators, follow through until you get to where a Storm Trooper is guarding a door. Defeat him and the door will open. Go through it, but do not go to the left to the Millennium Falcon. Defeat all the troopers that you can kill from the door's passageway. Then, go right to the wall. Duck so that the camera goes behind you. Look into the room with the Millennium Falcon. On the other side of the room, you will see Darth Vader and Obi-Wan in a lightsaber duel. If you go forward, you will see the movie scene of Obi-Wan being defeated by Vader.