Thanks cutnshut
The music when R2 and 3PO land on Tatooine is a version of Aranjuez by Isao Tomita:
http://www.youtube.com/watch?v=SILF8CrhoKo
All the music titles are in the end credits of the edit.
The "Adress me as Lord Vader" is from the VHS video board game, with JEJ doing the voice (and Prowse being behind the mask by the way):
http://starwars.wikia.com/wiki/Star_Wars:_The_Interactive_Video_Board_Game
video footage from this game are also used when Vader talks to an officer through a TV screen and then leave Tarkin to search for the rebels.