If you want to know how to be Luigi I will tell you. First you finish the game than you go to to the profile menu and you hold L and R as you open you profile and you will see Luigi. If you save when you play as Luigi it won't work so you have keep on holding L and R everytime you want to be Luigi and to be Mario just do not hold L and R just do what you always do just go on. I hope this works for you because it works for me. THIS IS ONLY FOR NEW SUPER MARIO BROS AND NEW SUPER MARIO BROS 2 NOT ANY OTHER GAME.