Other mistake: On the "Mario's Greatest Movie Moments" DVD of this series, from the main menu, go into the trivia game. The fifth question asks you about the Super Mario Bros. Super Show episode 'Count Koopula.' It asks you "What's room number that the Mario Bros. were put into in Koopula's Castle?" It's supposed to say "What's THE room number that the Mario Bros. were put into in Koopula's Castle?"
Continuity mistake: When the Mario Bros. speed up their car to get to the rebel fort, in one shot both of Mario's hands are on the steering wheel, and in the next shot his right hand is on some sort of lever that makes the car go faster. Luigi's hands also change position in these shots. (00:17:45)
Continuity mistake: When Mario, Luigi and Toad say goodbye to the Princess, Toad is standing at the front of their car, Luigi in the middle, and Mario at the back. Two shots later, the order changes to Mario at the front, then Toad, and Luigi at the back of the car. (00:15:10)