1. Do you know the name of the ballet with a boy named Fritz and a girl named Clara?
-the reason why you don't use does you is because structurally it doesn't make sense. Never use does you together, when asking a question.
2. Tony said that baseball practice had been changed to Tuesday at 7:30.
- for this one there are several ways to correct the sentence. You can use the words : was changed, had been changed, had changed. It just depends on when the comment was made to the other person.
Hopefully this helped.