We were at OKW with a stroller, and we didn't request 1st floor. Never again.
We stayed at PORS May 2005 with 2 small kids (double stroller) and we requested 1st floor building 14 (AB). We got it and was very happy. Close to the main building, parking and good location. However we were right next to steps instead of a ramp, so we had to enter from the other end or put it up 3 small steps. It wasn't bad.
YES request 1st floor. It was very quiet, no problems with noise above us. One night the lock door was noiesy (kids, meltdowns ect... but it was early like 8:30 and we mostly were never in the room at that time otherwise. Most of the time my kids were already sleeping when they got back to the room, so not having to carry them and the stroller up the stairs is a good thing.
Good luck.