Hi Melinda,
I love questions about dining at Walt Disney World!
Personally, I think your choice between Magic Kingdom restaurants is an easy one considering the ages of your sons. The Crystal Palace is a must-do experience with small children. Because the Crystal Palace offers a buffet, you will have no worries that your boys will find something they will enjoy eating. Beyond that, the pictures you will take with your sons and Winnie the Pooh and friends will be priceless. I'd call (407) WDW-DINE to book that reservation at the Crystal Palace pronto!
Your other question, about choosing a signature dining experience, is harder for me to answer. Jiko, California Grill, Flying Fish, and Artist Point are all wonderful restaurants. I suggest you check out the
menus at each of these restaurants on
www.disneyworld.com to see if there is a kind of food that is more likely to appeal to your family. If the menus looking equally enticing, I would probably choose to book a reservation at the California Grill because of its location. Situated atop Disney's Contemporary Resort, you simply can't beat the views of the Magic Kingdom from this restaurant! Ask for a table near the window.
Good luck planning a magical Walt Disney World vacation for your family, and don't hesitate to post more questions if there's anything else the Moms Panel can answer for you.
Jill