Hi Brian,
Thank you so much for visiting the Disney Parks Moms Panel with your question! How exciting to be planning your first visit to Walt Disney World. Let me offer you some thoughts on the theme parks.
I suggest that you start by watching the
Walt Disney World online planning video. This will give you an idea of what there is to experience in each of the four theme parks. Given the ages of your children, I would have them watch it too, to see what they are the most interested in.
I do generally suggest that on a first visit, that you be sure to head to
Magic Kingdom. This theme park is where the magic all began at Walt Disney World and has so many attractions! After that, which parks you visit will depend on your traveling party and their interests. For example, if anyone is a Star Wars fan you will want to head to Disney's Hollywood Studios, which is the headquarters for all things Star Wars at Walt Disney World. If you have animal lovers in your group, a day at Disney's Animal Kingdom to see exotic animals is in order. Finally, if your family is interested in the countries of the world, head to Epcot to wander around World Showcase sampling delicious fare.
If this was my first trip, I would likely try to plan one day at each theme park. A possibility is to choose the theme park that you think is the one that your family is least interested in, and plan that for your fourth day. When you are at Walt Disney World, you can decide instead to head back to Magic Kingdom that day if you feel like you did not get to experience everything you wanted to on your first day at Magic Kingdom.
I hope that these thoughts are helpful for you, Brian! Have a great time planning your magical vacation, and please do let us know if we can provide any further assistance!