Hi Juli! There are so many great character dining experiences offered at Walt Disney World. You did not mention if you have girls or boys or both so I will just offer some thoughts on my favorites!
Cinderella's Royal Table is very popular as what can be more magical then eating in the Magic Kingdom castle! But if you are looking for another great princess meal please check out the Akershus princess meals in the Norway pavilion in EPCOT. There you will most likely meet and greet Belle, Jasmine, Snow White, Sleeping Beauty, and Mulan. The Grand Floridian has the Wonderland Tea Party with Alice and the Mad Hatter and also the 1900 Park Fare breakfast or dinner with stars such as Mary Poppins and Cinderella and friends.
For the general famous Disney characters my favorite location is at the Contemporary and Chef Mickey's. Here you can find Mickey, Minnie, Donald, Goofy, and Pluto for dinner. Please click
HERE to read more about all those that are offered as there might be a favorite character of yours that you can meet at one of the locations!