Hansel and Gretel (1954)
This puppet-animated movie isn't based so much on the Grimm fairy tale as on the opera version by Englebert Humperdinck. (No, not THAT Englebert Humperdinck.) It features the music from the opera, alternating between spoken dialogue and arias in English, adapted from the German libretto. (At least one legitimate opera star, Anna Russell, provided a voice--she plays the witch.)
The story's altered a little bit, as it was in the original opera. Hansel and Gretel aren't abandoned in the woods through the machinations of a stepmother out to kill them--their otherwise loving mother loses her temper at a kitchen accident and sends them to pick berries in the woods and get out of her hair for a while, where they get lost and fall into the witch's hands. There are some lovely bits with the Sandman, a Dew Fairy, and a chorus of angels.
Michael Myerberg, the director, animated this with "kinemins"--puppets operated by electricity. The miniature sets are detailed and enchanting...but the puppets themselves look rather weird, without the winsomeness you'd usually find in, say, the Rankin-Bass figures. There are also some head-scratching moments, such as when the household furniture comes alive to dance with Hansel and Gretel.
It does have some elements to recommend it--the beautiful score from the opera, for one, and Lord knows I'm all about introducing kids to classical music. But it's also got enough whacked-out elements to balance it.
In short...this has more than enough weirdness and slight creepiness to be eminently riffable. See for yourself: https://www.youtube.com/watch?v=G1eaCHlCeBU&t=141s
Mike Tanner commented
OMG. THIS MUST BE RIFFED. I just saw this via Amazon Prime and it's absolutely glorious. The puppets fall so far into the uncanny valley that they bypassed the cliffs and went straight into the uncanny Mariana Trench.
Sometimes the puppets honestly look like they're going to steal your soul so they can eat it like candy.