I would suggest the 1900 Park Faire character breakfast at the Grand Floridian. It is more of an adult setting than most of the character meals, and the atmosphere is a little more subdued than most of the other character breakfasts. We did this one with two adults and two older teens this year, and enjoyed it. (The Fairy Godmother granted me a wish when we took a picture with her--hasn't come true yet, though).
The other one that is good for older kids and adults is Donalds Breakfast at Animal Kingdom.
Chef Mickeys is fun, but very loud and lots of younger kids, as is the Crystal Palace. (Someone mentioned Garden Grill, but I believe they only serve lunch and dinner).