Music is the one right next to sports. Celebrity hall (the varsity tents) are right between sports and music, so depending on what part of music you're in you could be really close to the tents and the football field. If you're on the far side closer to movies then it will be more of a hike, but nothing that needs a bus ride. You'll catch the Disney buses at the front of the music resort. The allstar resorts get their own Disney buses, so you don't have to have a ton of stops on the way to and from parks.
We got put on the farthest side of movies one year and it was the longest walk! They have since added UCA buses to movies, so depending on what side of the music resort you are on, you may be closer to the movie buses. The resorts are all laid out the same with different themes, so there is practice space in all the resorts.
How was pop century? We've only stayed at Allstar and Caribbean.