It's a great idea, and I can personally attest to the success of Meet Me in Saint Louis, Singin' in the Rain, National Velvet, The Adventures of Robin Hood, and Calamity Jane.
It's kind of surprising how much young children are willing to give you the benefit of the doubt when it comes to your tastes in movies or books. They are willing -- indeed, sometimes eager -- to have their tastes molded by yours.
A few days ago, I found performances of the girls' favorite Burt Bacharach tunes on YouTube (here and here). They enjoyed those so much that they requested more of the same last night. I decided to try some scenes from Les Miserables. They were riveted.
Here's one they really liked. They don't know the story, so I'm guessing they liked it for its pretty melody and because they picked up on the drama of the scene. I stood behind them with tears running down my cheeks.
I'm a total dork, but I don't apologize. I've found that children are happy to forgive even the dorkiness, when it's a matter of discovering the things their parents really love.