Hi Leslie! You're so smart to be making an itinerary for your family's first trip to Disney World! I've found that having a plan really makes for a more relaxing trip.
You don't mention in your question whether you will have the Park Hopper option on your tickets. If you don't, then you should plan to visit the park each day where you have made your dining reservations. For instance, if you have a reservation at Cinderella's Royal Table, then you should visit the Magic Kingdom that day.
If you have the Park Hopper option, then you'll be able to visit multiple parks each day if you wish. Of course, you'll need to plan to be in the park where your character meals are located at the time of those meals, but you could choose to visit other parks before or after your meal. I recommend that you start planning your itinerary by taking a look at the calendars
here (click each
park and then click "calendar") to determine the operating hours of the parks
during your visit, as well as the times of any parades or shows you'd like to
see and the schedule of Extra Magic Hours for resort guests. Use that
information to decide which park(s) you'd like to visit each day. You may also want to visit an unofficial site like www.touringplans.com which has a Crowd Calendar that predicts park attendance levels for each day. Click
here to view another question I answered with more tips for planning your itinerary.
If you need more help planning your trip, come visit us again at the Moms Panel and give us more information about the dates of your trip and the dining reservations you've already made and we'll help you finalize your itinerary. Hope your first visit is magical!