Howdy Tabitha! What a fun question!!
While any of the resorts would be phenomenal, my vote would be for
Bay Lake Tower or
Disney's Contemporary Resort. Both resorts are AMAZING and I would encourage you to stay at either, in particular, because of the ages of your children.
1st of all, location, location, location! You will LOVE being able to WALK to and from Magic Kingdom! When your kiddos are tired and numerous Guests are making their way to the monorail, buses or boat, you can skip the lines and head straight to your resort.
The pools are great and there is a white-sand beach your kiddos might enjoy.
Chef Mickey's is a wonderful character dining experience located in the Contemporary. Guests at Chef Mickey’s may meet favorite Disney Characters including Mickey Mouse, Minnie Mouse, Pluto, Donald Duck and Goofy. It's a very lively restaurant and your children will enjoy the all you care to enjoy buffet. We currently have a 4 and 6 year old and Chef Mickey's is one of their favorite restaurants.
Thanks so much for your question. If you would like suggestions for other Resort hotels, please let me know. I'm so excited for you!! I know you are going to have a magical vacation!