Hi Jenny,
Thanks for visiting the Moms Panel! We love helping guests plan memorable vacations with their families.
You are going to have such a fun time visiting the Magic Kingdom with your little ones. As soon as you enter the park, pick up a "Times Guide" (located near the maps as you walk into the park). Specific character Meet and Greet times
and locations will be listed on there. You will be able to visit with Mickey and some Princesses right on Main Street at the
Town Square Theater.
You are correct that you will be wanting to spend the majority of your day in Fantasyland. There are a lot of attractions there that will be fun. Be sure to enjoy Mickey's PhilharMagic, The Many Adventures of Winnie the Pooh, Peter Pan's Flight and It's a Small World. You'll also want to head back to New Fantasyland and visit the Storybook Circus for the Casey Junior Splash 'N' Soak Station, Dumbo the Flying Elephant, Under the Sea ~ Journey of the Little Mermaid and Enchanted Tales with Belle.
Attractions that toddlers may enjoy in other areas of the Magic Kingdom are:
Tomorrowland: Buzz Lightyears Space Ranger Spin, The Astro Orbiter and the Tomorrowland Transit Authority PeopleMover
Frontierland: The Country Bear Jamboree and Tom Sawyer Island (great place to run around and burn off some energy)
Adventureland: The Jungle Cruise and The Magic Carpets of Aladdin
Hope this helps and have a wonderful vacation. Please let me know if I can assist you further,
Kaylene