I would highly recommend "Snow White And The Three Stooges," in this case. It's a perfect fit for the kids. My kids love it! It's the Stooges, it's in color, it's in widescreen. It's actually not that bad. Sure, it's a departure. But it's a good starting point for younger kids who are interested in the Stooges. The kids will love the fairy tale and won't forget the Stooges. I started mine with this movie and easily moved to The New Three Stooges cartoon series.
Also, "Swing Parade" is a good one for the kids. If they like music, that one's got plenty. My daughter, in particular, loves "Swing Parade." It's got Curly, too. Any of the scenes in "Swing Parade" that were not involving the Stooges, my daughter very quickly took an interest in the wardrobe of the characters, especially Gale Storm.
Isn't it amazing just how well-rounded their film career is?