The 3 All-Stars and Pop Century are the value resorts and are almost ALL virtually the same except for how they are decorated. Pop Century is newer and is much bigger, but like I said...all virtually offer the same value and such.
As for noise, you're going to get noise at any of the ones you stay at, but to be honest, I would guess you would get the LEAST amount of child noise at Music. I say this simply because sports is well...kids love gigantic footballs and basketball goals. Movies has the Dalmations hanging around, Buzz and Woody, among others. Pop Century has a giant can of play-dough, huge big wheel sitting around. Music has big maracas and a giant sax, not so much what young children would be more interested in.
But like I said, that's just a thought, and more so you are looking at four very same, yet differently decorated resorts.