Hi Coleen!
First trips are always the most exciting! I would make reservations for
Chef Mickey's which is one of my family's favorite character dining experiences. Characters that are usually found at Chef Mickey's are Mickey, Minnie, Donald, Goofy and Pluto. This buffet style restaurant serves delicious food and it's located at Disney's Contemporary Resort (which is only one Monorail stop from Magic Kingdom).
If your kids want the Royal treatment then you won't want to miss
Cinderella's Royal Table located inside Cinderella Castle at Magic Kingdom. This fabulous dining experience is super exciting because you're actually invited inside by Cinderella herself! And other Disney Princesses visit your table while you dine.
Advanced dining reservations are recommended because these are very popular restaurants. Click
HERE so you can explore all of the other fabulous character dining experiences that are offered.
Hope this helps and have a magical vacation!