Yakkity Sax is the only one for me. But not because of the moral itself (supporting a friend who likes something she's not very skilled at), but because That's not how the problem was shown!
They showed a problem about a friend being disrespectful of the rest of their friends by interrupting and sabotaging their jobs, and told us that the problem was her skills being poor??! No sir, the problem was her timing and disrespect!
At the end, the moral, which is actually a good one, had nothing to do with what the episode showed.