Finding Nemo cheats and cheat codes for XBox

Cheat mode
At the screen with the "New Game" and "Load Game" selections, push
Y, Y, Y, X, X, B, X, Y, B, X, Y, X, Y, X, Y, B, Y, Y.
If the code is accepted, you will see a  word "Cheat" on the screen.
Enter to the level selection screen and hit Start.
You will find the unlocked "Cheats" option. Choose it to find options 
to unlock all stages and another cheats labeled as "?".

Secret clue
While on the Mount Wannnahockaloogie level, look for an old brown sign. 
Dart behind the sign to score an important clue.


Untested cheats:

Invincibility:
At the screen with the "New Game" and "Load Game" selections, push
Y, X(2), B(3), Y(2), X(3), B(4), X, Y, B(3), X,B, Y,B(2), X, B(2), 
Y, B, X, B(3), Y. 
Note: The invincibility does not occur on all levels. 
Pause game play to access the cheat option at the level selection menu. 

Credits:
At the screen with the "New Game" and "Load Game" selections, push
Y, X, B, Y(2), X, B, Y, X, B, Y, X(2), B, Y, X, B, Y, X, B(2), Y, X, B 
Pause game play to access the cheat option at the level selection menu. 

Secret level:
Press Y, X, B(2), X, Y(2), X, B(2), X, Y(2), B, X, Y, X, B(2), X, Y 
Pause game play to access the cheat option at the level selection menu.