The site the first poster linked-to is the one we used to plan our stay at PORS in 2012, and it's a great resource!
My advice would be, if you have a standard room reserved, request building 16 in Alligator Bayou (closest to the preferred buildings without actually being preferred). We did, and got building 17, which was close enough! We could have an easy walk to the main building to refill mugs or visit the gift shop or lounge, but we could also cut across a parking lot and easily reach the main bus depot. I don't know if this is still the case but back then, the main (South) bus depot was generally the first stop for incoming buses headed to the parks, so if you wanted to have the greatest chance of getting a seat (as opposed to standing, or even having to wait for another bus if the first filled up), that was where you wanted to get on the bus if you could.
(EDIT: A previous poster and the unofficial PORS website indicate that the West depot is now the first pick-up for park-bound buses, so if being first on the bus is a priority, you might want to request buildings closer to it - e.g., 24, 25, 26 or 34).
Also, if you have any inclination to visit Disney Springs, the boat launch from PORS is extremely convenient and enjoyable.
A transportation option: POFQ and PORS are connected via a walking path. If you heading back to the resort from a park and would rather walk for a few extra minutes than wait for a few extra minutes, keep an eye on the POFQ bus stop as well, if a bus gets there first, get on it. Once you get off at POFQ, you can take a scenic stroll (about 10 minutes at a leisurely pace) up the Sassagoula River path to PORS (coming in at the mansion end). I've also read about people walking down the path in the morning just to get some beignets at the POFQ food court!