Hello, Perry!
Well, early birthday wishes for your little guy as you plan his first trip to Walt Disney World! Wow! What a treat!
If you really want this to be a special trip, consider booking a two-bedroom at one of
WDW's Deluxe Villas. These villas have fully-equiped kitchens, washers and dryers right in the room and plenty of living space to keep everyone happy. Bay Lake Tower at Disney's Contemporary Resort is the closest to Magic Kingdom, and enables Guests to walk to the monorail station (just a few minutes' walk via the covered Sky Way Bridge) at the Contemporary Resort for quick access to Epcot. (Your group could also fit into a one-bedroom villa; both the sofabed and sleeper chair in the living area are quite comfy!
We also love stays at Disney's Animal Kingdom Villas-Kidani Village; a savannah view is a highlight of every day. Samawati Springs pool and Uwanja Camp will amaze you, too. While it's a magical resort, it is further from the other parks, so keep this in mind while considering your stay.
For quick access to Epcot and Disney's Hollywood Studios, try Disney's Beach Club Villas. You'll be able to walk to Epcot in five minutes and can either walk or take a boat ride to HS. The Boardwalk area there, too, is great for dining and entertainment, and you won't believe how spectacular the pool, Stormalong Bay, is.
If you'd rather stay in one of the spectacular
Deluxe Resort Hotels, any adjacent to the monorail will give you great access to MK and Epcot. Animal Kingdom Lodge provides the best access to AK and any of the fabulous Deluxe resorts in the Boardwalk area can get you to Epcot and HS quickly.
Send more questions as you consider your resort options; I'd love to help you pick the right one for you!