CNN/Travel has a helpful article about dining at WDW with kids.  The article is worth a read if you’re planning a Walt Disney World vacation with kids.  It briefly mentions dealing with food allergies and special diets:

When I booked reservations, I was asked if anybody had allergies so that the information could be noted. Don’t be shy about dietary requests either. Walt Disney World gets more than 7,000 such requests a month — just call a few days in advance if you need meals free of gluten, eggs, dairy or peanuts, for example. Another tip: Whether you are at Disney World or a favorite city this summer, make reservations. With young kids, earlier is better. You can always change them.

Some more advice from the article:

Another tip: If you are planning to spend your entire time at Walt Disney World (or Disneyland in California) consider the well-priced meal plans that you can add on to your room/tickets package that even include a daily “snack.” Disney officials say you can save as much as 40 percent at more than 100 restaurants and quick-food places throughout the resort.

There’s one drawback: If you have any junior foodies under 10 in the group, they’ll be limited to the kids’ menus. The other drawback: It seems so many people are opting for the dining plan that reservations are needed. Remember, you are really booking a “priority seating” time, which means you may need to wait when you arrive, as we did several times.