Hi Jennifer!
A great choice for breakfast with the princesses is
Akershus located in the Norway pavilion at Epcot. Akershus offers a photo opportunity when you first arrive and the photo package is included in the price of your meal. They have a buffet with pastries and fresh fruit and the hot portion of your meal is served family style and is all you care to eat. Four or five princesses will visit your table during your meal for pictures and autographs.
My favorite counter service locations at the Magic Kingdom are Cosmic Rays and Columbia Harbour House. Cosmic Rays has a wide selection of choices ranging from chicken and ribs to salads and wraps. Columbia Harbour House has great salads and sandwiches.
At the Animal KIngdom, I enjoy the food at Flame Tree Barbecue. Animal Kingdom also offers something called Picnic in the Park. You can order a meal from a variety of options at the Island Mercantile shop and then you pick it up at a specified time at the Kusafiri Coffee Shop. After picking up your meal you can enjoy it at any of the picnic spots throughout the park. The Picnic in the Park accepts quick service credits, but only adult credits. For example, if you order a meal for three (2 adults, 1 child) you will have to redeem three adult credits.
Epcot offers so many choices based on your individual tastes. The World Showcase has lots of quick service options, some of which are located in Mexico, Morocco, Japan and the United Kingdom. In Future World, Sunshine Seasons located in The Land pavilion has different areas that offer a good variety.
At Hollywood Studios, some nice places for a variety of choices are the ABC Commissary and Backlot Express.
I hope this helps with your planning! Have a wonderful vacation!