These fairy tales are known and loved by millions of people all around the world. I think a global premium set would be right for this, although I was initially thinking about a regional German set.
I suggest 6 stamps, each representing an item/building from a well-known tale:
Cinderella: A glass slipper on the stairs
Snow White: A red apple (similar to the iOS achievement stamp)
Hansel and Gretel: A gingerbread house
Little Red Riding Hood: A red cap
Rapunzel: A tower with long, golden hair
Sleeping Beauty: A spinning wheel
If possible, please don't make these stamps too cartoon-ish. It would be great if they looked more elaborate or life-like.