At the main menu of disc 1, where it says PRESS START, press left, right, up(2), down, circle.  If entered correctly you should here a sound.   Then go to options, extras and "ART GALLERY" will be selectable.  For disc 2 press, up(2), R1(3), square. For disc 3 press,  L1, R2, L1, R2, L1, square at the main menu. | 
Submitted by Mike
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