Regarding the difference between SSR and OKW - I would also vote for SSR if your 2YO will go in a stroller. (that is the only way mine will fall asleep while we are away - a walk in the stoller). For stroller walking - SSR is much better - I found OKW a bit cramped and always seemed to be close to parking areas or roads. Another perc is SSR has elevators to roll the stroller in - OKW doesn't if you are on the upper floors.
As for location - I have stayed in both Congress Park and the Springs. I liked CP because it was a quick walk over to Downtown. But, I liked the Springs better cuz it was closer to the main buildings and restaurants.