While my poor 3 to 4 10-minute miles don't compare to a marathon, I LOVE OKW. You can hit a path back behind the South Point units and wind back through to SSR. I have never had any problems with the layout of OKW. We stayed at SP, which was pretty far from the main building, but it was still only a 10 - 15 minute stroll. DD, who is 4, had no problems with the walk at all. If it's raining, you can hop a bus, which will take you to the main building.
I've never stayed at PO, but have been to CS and agree with the previous post. CS seems more spread out to me.
Enjoy your stay at OKW. If you're looking for a relaxing stay, you've found the right place. I like OKW more and more each time we visit and could spend the entire stay just relaxing there. The tennis courts are nice, they have a workout facility that's small, but nice. Just a lovely resort overall.