I think I'd begin by looking at which restaurant has your children's favorite characters:
My family has always loved
Chef Mickey's at the Contemporary Resort. As young children, they were amazed at the monorail running through the resort then they got to have fun dining with Mickey & his buddies. It has a great atmosphere & a chance for the guests to enjoy themselves while dining.
If your children are fans of the Disney Channel's Little Einsteins, Jake the Neverland pirate, Handy Manny, & Special Agent Oso,
Hollywood & Vine at Disney's Hollywood Studios offers a lunch meal with these characters.
My sons always had a special place in their heart for Winnie the Pooh and his friends when they were little. Because of this, the
Crystal Palace at the Magic Kingdom is a lovely place to dine for either lunch or dinner.
Donald Duck and Daisy Duck as well as some of their friends are at
Tusker House at the Animal Kingdom for lunch. One thing that this restaurant offers is a chance to try some African flavors, which my family absolutely loves.
Chip 'n Dale & some of their friends are at the
Garden Grill at Epcot for dinner in a restaurant that actually slowly spins allowing guests to see much of the Land Pavilion. It is also served family style instead of a buffet, which can be nice when dining with toddlers.
There are certainly more places, too, but I hope this gives you some options to get started with your planning a character meal for lunch or dinner. Please let us know if we can help again.