We used Fairy Godmothers once when DH had a conference at WDW and there was a dinner that included spouses. We had 1 room at CSR. The sitter brought a suitcase full of age appropriate toys for DSs (3 and 5) to play with her. When we returned, she was sitting on the end of one of the beds reading a book by flashlight! It made me really nervous to leave DSs with an in room sitter but it turned out fine.
If DSs had both been old enough for the Neverland Club or one of the other resort kids' clubs, I would have put them there. On a later trip, DH and I ate at California Grill while we sent DSs to the Mouseketeer Club at the CR. DSs had a blast- there were board games, video games, arts and crafts, TV with VCR and stacks of Disney movies, and some fun, energetic CMs. For a 7 year old, I would highly recommend one of the kids' clubs rather than an in-room sitter becasue he will have so much more to do and some other kids to hang out with him.