Hello Tina! Well the good news is you'll be able to enjoy Disney during the magical holiday season! As far as your dining reservations, I hear your pain. The one downfall to making a last minute decision to head to Disney is the lack of availability at some of the more popular restaurants. Many guests have booked their reservations months ago.
The only thing you can do is to keep checking the
restaurants page (or calling 407-WDW-DINE) to see if there are any cancellations. Some of the restaurants do have late seatings for breakfast so you may want to be flexible. There are times when I can't get an early morning breakfast reservation but I am able to get one in the 10:30-11:00 time frame. In that case we'll have a quick snack in the morning, visit the parks and enjoy a wonderful brunch.
You are also probably wondering if you can walk up to a restaurant and ask to be seated. That is always and option but to be honest, I haven't had much luck doing that so if that is something you want to try, you may want to make sure you have a back-up plan.
Good luck with your reservations! Diane