We love Goofy's Kitchen! You get a lot of the classic characters, plus a few random ones thrown in from time to time...plus we like having a buffet at our fingertips. The food's not amazing, but it's standard buffet food.
I can also recommend Ariel's Grotto if you want the princess experience - the food is better than Goofy's Kitchen.
I've heard great things about Storyteller's Cafe too...oh and I hear the Plaza Inn is great for a character breakfast! (I haven't actually eaten there though...just, um...well, lets say I've been there more than a few times helping out some friends.
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