At the start screen press X,L(trigger), X, L(trigger), X, X, L(trigger), R(trigger), L (trigger)
After you finish, the level select option will appear and you will have access to all costumes, dog tags, movies, & artwork.
p.s. - In order to get invulnerability you may have to repeat the code a few times and start the game to see if it works.
When you do this pause during gameplay and you should see the cheats options to turn invulnerability on, if not you will have to try the code again at the start menu and continue to check.
But it does work!!
Added by: Terrell , ID#659