Hi Danielle,
With your trip nearly here and over a holiday break, many of the popular restaurants may be booked up already. The first thing I would do, is to decide a possible schedule of what parks you'd like to visit on specific dates. If you click
here, you can see the hours of the parks. You'll need to decide if you want to take advantage of Extra Magic Hours. Personally, we like the morning hours, but we avoid the evening hours. You may also find that picking a park that has no Extra Magic Hours can also be a way to find smaller crowds (we've done that as well).
Once you've selected the days you'll be visiting specific parks, you'll want to visit
here. You'll be able to select the park you hope to dine at on a specific date as well as your dining experience (most likely Casual Dining and/or Character Dining). I'd then offer a time such as lunch or dinner and then just see what is available. You may have more luck eating at off times, too. I'd aim to have a table service reservation each day since you are on the dining plan (just an fyi, the signature dining locations take 2 credits a meal). If this seems too complicated, you can call 407-WDW-DINE and a cast member could help you as well.
You may also want to consider visiting nearby resorts for dining (which are beautiful now with Chrismtas). At the Magic Kingdom, the Contemporary, the Polynesian, the Grand Floridian, and the Wilderness Lodge are nearby. At Epcot & Disney's Hollywood Studios, the Boardwalk, Beach/Yacht Club, & Swan/Dolphin are nearby. At the Animal Kingdom, the Animal Kingdom Lodge is nearly next door.
Have a wonderful trip, and thank you for visiting the Moms Panel.