In the main menu go to the bonus menu then go to cheat codes then enter these codes then to activate go to the cheat menu in-game then turn them on.

Effect	Password
Allows Buzz to use his laser in all the story levels	BLASER
Play the game with an old movie effect	OLDMOV
Squeeze Toy aliens wear 3D glasses	3DGLAS
Woody wearing his bandit outfit	BANDIT
When woody lands on ground snakes come out	Snakes