We just got back last week from Pop, and we stayed in the 90's building on the 1st floor overlooking a small grassy courtyard and the small edge of the 90's parking lot. At first, I was disappointed, because it is the farthest from the food court and bus stop, but once we got in the room, I was fine with it. The resort really isn't as spread out as I had heard. We didn't have a long hike to our room- in fact, the whole resort is surprisingly compact! The walk to the bus stop in the morning took less than 5 minutes (we cut through the parking lot), and the 80's/90's pool was feet from our 1st floor room door. We headed over to the 60's pool a few times, and it was a really nice walk past the lake and through the 70's courtyard to get to it. Took around 5 minutes, with the Pop Jets fountain along the way.
If you want to be as close as possible to the food court and busses, the 60's buildings or the 70's rooms closest to the Classic Hall are great.