Hi Breanna,
I think every hotel at Walt Disney World is a great place to stay with very young guests. However, if I can only recommend one, then I have to recommend Disney's Beach Club Resort. It is on Crescent Lake between Epcot and Disney's Hollywood Studios. You can walk (short to Epcot; very long to the Studios) or take a boat to either theme park.
I recommend the Beach Club for young guests for one thing:
Stormalong Bay. Stormalong Bay is absolutely amazing. It is a sand-bottomed pool covering about 3 acres. The Guppy Bay Kiddie pool has a sand island in the middle where young guests can make sand castles. Last summer I had a very hard time getting my 5 year old and my cousin's baby out of the pool; they would have been happy to spend their entire vacation there!
However, you might also consider staying at a Magic Kingdom Resort. With very young guests, you may spend a lot of your time in that theme park. Staying at a Magic Kingdom Resort would allow you to get back to your hotel room quickly for naps, etc. The Contemporary Resort, Polynesian Resort, and Grand Floridian are all on the Magic Kingdom monorail line. Disney's Wilderness Lodge is another Magic Kingdom Resort that can be reached via a boat from the theme park.
Have a magical vacation!