Disney does not own Snow White, Cinderella, or Beauty and the Beast. They do own their own particular realization of those stories. As long as you aren't blatantly copying the Disney movie version (or someone else's specific work), there's nothing to worry about. Actual films have been done with the same public domain sources that Disney mines. There's sensible respect for copyright and then there is paranoia. Also, this place has plenty of very derivative work already, especially when it comes to reworking the Lord of the Rings map.

Nonetheless, Bogie has posted the guidelines for this challenge, so basing off existing maps or art is out this time around. I can see no objection to this as a challenge restriction.