Hi Dana,
The newest resort would be the
Bay Lake Tower at the Contemporary. Having just stayed there, I can tell you the rooms are gorgeous and there are a ton of amenities. The adults in the party will like the pool, big water slide, and hot tubs. The four year will have a blast with the mini water slide perfectly proportioned for them and the splash zone. There are also tennis courts, shuffle board, nightly movies under the stars, and plenty more. The other recent addition is the
Kidani Village at the Animal Kingdom Villas. The villas may be a good option with 4 adults because you can book a one or two bedroom.
You should also check out
Disney's Caribbean Beach Resort. Many of its rooms were recently renovated in a pirate theme. They are pretty impressive as is its recently renovated pool area. It also has smaller water slides for those under 48 inches tall and a large splash area.
You really can't go wrong with any of those three resorts.
Have a great vacation
Michelle