Hi Gina,
I am sure that we can find a great place for you to celebrate your twins' birthday! I suggest that you start by visiting the
Walt Disney World Dining website. Once you are there, set the date, time, and party size. I just did this and set the date that you are looking for, chose "Dinner" as the time, and I selected a party size of four as a starting point since I was not sure how many are in your party. The restaurants that I mention below all have availability on your twins' birthday.
If you are going to be at Disney's Hollywood Studios that day,
50's Primetime Cafe has availability. This fun restaurant reminiscent of mid-twentieth century Americana includes cast members who will interact with your family in a truly hilarious manner.
Hoop-Dee-Doo Musical Revue also has availability that evening. This foot-stomping, hoot-hollering dinner show features delicious grub and enjoyable entertainment. For a different type of birthday celebration, if your children are adventurous eaters, consider
Boma - Flavors of Africa at Disney's Animal Kingdom Lodge. This bountiful buffet features African-inspired fare.
There are many other restaurants with availability showing on the website at Walt Disney World that evening as well. I do suggest that you make your dining reservation as soon as you can, and note on the reservation that you are celebrating birthdays. While there is no guarantee, you never know when a little extra pixie dust may be sprinkled on your celebration! Please do let us know if you have any further questions, Gina.