Regain lost life:
Immediately enter the inventory screen after losing a life. Press A + B. The phrase "Start Again" will confirm correct code entry. Select your character and resume game play with no lives lost.
Walk like an Egyptian:
Leave the screen holding a box and hold the D-pad. When you get to the next screen, your character will not be holding the box, but he will continue to walk with his hands in the air above his head.