On the pause menu push:

Down, Down, Down, Down, L, right, down, right, L
For repair bot

Start, start, down, left, right, down, left, right
For blue gangun

Start, start, down, down, down, down, down, down
For general greivious

Start, start, up, up, up, up, up, up
For the red R2-D2

Start, start, up, down, up, down, up, down
For a black (or blue) R2-D2

Start, start, down, up, down, up, down, up
For the orange robot on a hoversled

Alrite heres some color changing light saber cheats.
To activate cheats pause the game and enter the cheats you want.

Black light saber:
L,L,R,Start
Blue light saber:
R,R,R,Start
Green light saber:
R,L,R,Start
Purple light saber:
L,R,L,Start
Red light saber:
L,R,R,Start

Enjoy the different colored light sabers.

~skyline_2fast_luffy~

Enter a level and pause the game.Then press Start,Start,Down,Up,Down,Up,Down and up in that order.Yoda will confirm your cheat.Resume game and you will be a battle droid on a hoverbike.The droid can hover like Jango Fett and is able to jump as high as Obi-Wan.

To be him go to in game pause and go in this order start,start,and repededly press down untl the beep then I think his L button is his gun but I am not sure.

T Be a Geonosian Warrior go to start and press in this order- start, start, right, down, right, down, left, up.