I 2nd the vote for the Grandstand. Its about 8 -12 minute walk depending on how fast you walk. BUT you can hop on the bus and ride around to the main area. The Grandstand has a nice pool area.
If you have the refillable mugs you can refill them in the snack bar at the pool until I think 7 p.m. when the bar closes.
I think if you want to ride the bus from the main area back to the Grandstand that you would have to hop on the DTD bus. At least that is the way it use to be it might have changed. Someone correct me on this.