Krusty's Super Fun House, like pretty much all the Simpsons games, is pretty tough. You have to take Krusty on a tour of the rooms in his Fun House to rid it of an infestation of purple mice. It's a puzzler, of sorts.
But say you get tired of the puzzles, or you just give up. You could start the game over and change the default password of "HI KIDS"
to the much less obvious " JOSHUA " (with a space at either end)
Which will let you enter any door in the Fun House you want. So just enter and immediately leave all of the different areas to instantly clear them. Then, head to the exit and marvel at how such a tough game could have such a lame ending.
I warned you!