Answer: He fixes the hyper drive on the "Millennium Falcon".
He, of course, does all of these things, but in different movies. He realizes that the Empire deactivated the hyper drive on the Falcon and ignores C3PO's complaining about his detached legs and fixes it and lets the crew get away.
He also fixes a hyper drive in "Phantom Menace", saves Padme from molten liquid in "Attack of the Clones", saves them from a garbage chute crushing them in "A New Hope", and gets doors open on the forest moon of Endor in "Return of the Jedi".