The big pool at OKW is nothing great. It is just a big pool. It is shaped in a round "T" for the lack of a better description. There is a bridge that goes over the point of the intersection. Your teenagers may not think it is that cool. My DD is 10 and is bored without a slide and lack of theme. If I were you, I'd plan to pool hop if they want to swim lots.
As for eating, your choices are Olivia's and Good's. I have never eaten at Olivia's - too pricey and not our kind of food. Good's is great if you want fast food. They have a great chicken salad croissant, nachos, super burgers, hot dogs, fruit. The food tastes great and is reasonable for Disney.
Have fun!!!