Welcome! You can learn so much about EVERYTHING on this site. I know I could never have planned our first trip without it and I am now busily planning my second.
You didn't mention when you were planning to go. Check out the Restaurant boards on this site for Priority Seating tips. There is a separate link for Cinderella's Royal Table - I think your girls would LOVE that . Mine most definitely did and we plan to do it again. The other princess meal is at Epcot and there is also a thread for that. Make sure you read up on those if you are interested, because you must try for those EARLY. The other restaurants are not so difficult!
Any questions you have, just ask here because you can count on some terrific information! Also, The Unofficial Guide to WDW is my favorite planning book!
Have fun planning!