I've done both multiple times and I would recommend the Plaza Inn Minne and Friends breakfast for maximum character interaction. The Storytellers breakfast is also good but doesn't have as many characters. Also, I would say the quality is about the same at both.I gave Disney Dining a call, the brunch is $37/adult and $24/child.
Still debating on this and Plaza Inn breakfast...our hotel has wonderful free breakfast, so it's hard for me to chose to pay for breakfast...that's why I was leaning toward the brunch, but it's really about the character interaction isn't it?!