In the Debug Menu you'll be able to select the stage you want to go to,
the amount of lives you want, the amount of health you want, th actor
Wait till the title screen appears and enter this code: AAAAX BBBBY XXXXA YYYYB ABXY.
You've probably noticed a pattern.
Invinvibility
Enter the Debug Menu code. When your playing the game,
on controller 2, press Select, A, B, X and Y simutainiously.
Sound Test
Wait until the LucasArts title screen appears then simutainiously press
A, B, X, and Y. Then press Start.
Credits
Wait until the LucasArts screen appears then press A, B, A, B, A, B, A, B.
Unlimited Lightsaber Usage
When the Game Start screen appears, press Y, Y, X, X, A, B, X, and A. You will now have unlimited use of the lightsaber.