Chef Mickey's character meal is a must! We've done it twice, and as another post says, its a tradition for us to do that on our first night...last time we checked into the Polynesian, unpacked, took a quick swim, then took the monorail over to the Contemporary for dinner at Chef Mickey's....its a great way to start the trip!
Pooh character meal at Crystal Palace, we've done twice, and had great experiences both times. First time, my then five year old daughter cried when we had to leave....it was one of those rare circumstances where she got some special one on one time with the characters in between breakfast/lunch when everyone else had left! Rare and magical!
Character breakfast at Ohana at the Polynesian....was very nice. Not our favorite, but very nice. The general atmosphere and food there is great any time of day.
We want to do the princess breakfast at Cinderella's Castle...coulldn't get reservations, so we just had dinner there, without characters. In our opinion, it was worth it just to eat in the castle. Will try for the princess breakfast for next time...but if we can't get it, we'll try fo the new princess breakfast at Epcot, if they continue it past the trial period.