Depends on what you will enjoy doing most and for how long. While some
DVC pools offer more than others, my kids at that age had fun at any pool. My recommendations regarding location, based on my past stays:
Beach Club: nice if you like having active pool days, Beaches & Cream is fun, restaurants in resort not great but can walk over to Boardwalk/Swan/Dolphin.
Boardwalk: pool is quieter than beach club but has its usual slide stuff. Boardwalk area is fun to spend a day or so.
SSR: I believe most/all rooms now reno'ed. Walkable to Disney Springs, but distance may be further depending on where you are assigned (but can take internal bus system to get closer). Food options on site nothing special in my opinion but reasonable, and are located in the main building so you may be far. But if you go to DS you're fine. Multiple pools on resort that were quiet.
OKW: Very quiet. Like SSR, a spread out resort. Haven't eaten at Olivia's but I here it is good. Have to take boat to SSR. Very quiet.
Poly/BLT/GF : all nice for sure but higher points mainly based on location to MK. Poly pool better themed than BLT's and GF seems to be relatively easier to snag a studio. Have access to all the very good food options along the monorail loop. Can't go wrong with any but points a bit higher per night.
Yet to stay at Riviera but looks beautiful and skyliner could take you to Epcot and from there could walk to boardwalk.
In short, I don't think you can go wrong with any option.