Our family's favorite resort is the Polynesian-they have a volcano water slide and I think the pool is pretty nice (we haven't stayed there in 6 years b/c we can't afford two rooms-our 6th member (little brother) past age of three:/-but I know the pool is the same). Since I haven't stayed there in a while like I said, I can't tell you for sure if these next things are still true, but I'm sure at least one of them is. They have a beach at the Poly, and when we were there the lifeguards would gather up some kids and play kickball-this would be great if you have younger siblings. Another thing is that if you are the first one in line for the volcano slide in the morning you get crowned king of the slide for the day with a special ceremony. My brother did that-he was there before the slide even opened! The great thing about that special moment is that we were done with the parks and were just going for a swim before we had to leave that afternoon. But anyway it was really fun-that's the one that I can't say they still do-I really hope they do, but you'd have to ask someone else (thank goodness for the disboards, right?).
The volcano slide is very fun and it's big! (at least from what I can remember). But the pics will show you what I mean, as the theming is great. The pool is zero-entry as well, which is nice.
I know you asked specifically for a note on good pools, but I'm going to go ahead and tell you why I like the Poly as a resort as well. For us, it's the theming and atmosphere. You get leighs when you check in which really helps with the feel of it. Also, I know this costs extra but you can get a room that has a great view of the volcano slide-we had it last time we stayed there. Also-for us the smell really goes well! It just smells tropical (that nice fresh smell, I mean). Also they have a dinner show; I forgot what it's called though. might already know this but it is a monorail resort so you can get to Epcot and MK faster. Honestly I think if you like the tropical Hawaiian feel as much as we do it would be a good place to stay.