To get all of the cars in the game, enter the following code at the Cheat menu: MONKEYSPOILERS
To get all of the gadgets, go to the Cheat screen and enter this code: GADGETDEAROUT
At the Cheat menu, enter the code CHIMPGIVEAWAY to unlock all of the tracks in the game.
To enable Kid Mode, go to the Cheat screen and enter this code: THOSEWACKYKIDS