Not an easy question, but here it goes:
Breakfast: Ohana (Polynesian) - especially with younger children! I love the kids marching around the restaurant in a parade, the food is really good and Mickey and Goofy are in Grass skirts...how much better can you get?
Lunch: Who has time for lunch? Well, since I'm dreaming anyway, I think I'd like to go to the 50s Prime Time Cafe (MGM). This is one of the best themed restaurants on property.
Dinner: California Grill (Contemporary) - The food is spectacular - the best I've had at WDW (I've been there several times - great each time) and the view overlooking MK is simply the best view in all of WDW. For a ramantic evening, you can't beat the sunset over Seven Seas Lagoon as you enjoy a nice dinner at CG.
Enjoy!