To unlock the Galactic Enforcer color set, at the level selection screen, press UP, RIGHT, DOWN, LEFT, A, B, Select. Then, select any level, and you will be in the "Galactic Enforcer" color set. Both Ben and all his alien forms will be black and white and official "Galactic Enforcers".
To unlock Master Control, you must first beat the game. Then, start a new game and collect all 30 Sumo Slammer Cards. Master Control will become enabled when you play a level on the "Insane" difficulty. It gives you unlimited Omnitrix battery, and the ability to switch between aliens without reverting back to human form.