I have not stayed in the Disney facing rooms or a room in one of the two-story buildings. We usually choose building two facing the pool or building 1 kid suite.
Between those 2, building 2 is definitely quietest. I usually request a room closer to the parking lot side of that building so I don't have to hear even a hint of freeway noise. The most noise we have noticed in building 2 was from some rowdy kids at the pool one night when we had a first floor room. The noise didn't go on too long or late though, and it wasn't anything worth complaining about.
Building one freeway side can seem noisy. I was surprised though that it didn't bother me as much as I thought it would, and I find it totally worth it if we're going to get the suite. I wouldn't bother with freeway side otherwise though. I would imagine that non-freeway side of building 1 (Disney facing) would be ok if you were in one of the middle rooms rather an an end room.