This is the code that unlocks everything. Guitars, songs, videos, EVERYTHING. However, SAVING IS DISABLED when the code is inputted and you must turn off your ps2 to turn off the effect.

BLUE, YELLOW, ORANGE, RED, ORANGE, YELLOW, RED, YELLOW, RED, YELLOW, RED, YELLOW, RED, YELLOW, RED, YELLOW

Press it in at the MAIN MENU screen in a quickly manner.