I am also wondering the same thing as my family is in the same situation
Also, does anyone know if there are any quiet pools? By the time we get to WBC, it will be my daughter's nap time and I doubt our room will be ready. I figure if there is a quiet pool, we can stake out a shady spot with a couple of lounge chairs and hopefully she can have a short nap there.
I haven't spent much time around the place during the day, but I'm thinking that the closest you'll get to a "quiet pool" will the be one at the hotel.
Remember that all the pools are between the buildings and the lakes. Unlike Disney where the resorts are spread out more like a campus, and the "quiet pools" will be a little ways away from the other pools and usually separated by some buildings or foliage, There aren't any real barriers between the pools that will help block the louder sounds that could be coming from other pool areas.
That said, Tower 5 has the lazy river and zero entry which is a large draw for kids and families. Tower 4's pool is a bit more adult, but also has one of the pool bars and a lazy river exit (from tower 5's pool), so it's likely to have it's own form of noise.
The Main building pool has a lazy river and kids splash area.
tower 3 has a slide, Kids splash area, and the other timeshare resort pool bar.
Tower 6 is zero entry, the Pirate ship pool, and has a slide.... so again, big family/kid draw.
That leave the hotel pool. It has a zero entry section and a pool bar.... but is a lot less themed and more open (not sure about shade TBH.... though the last time I was there was shortly after it opened, so I dunno if foliage has had a chance to grow out and create more shadey places since then). Just due to the nature of the pool, It's a much more "adult" pool and vibe which is less likely to draw the kids and families than some of the other pools at the resort..... That being said... as I mentioned, i'm not very sure of the likelihood of finding a nice shaded spot at this particular pool. also, it's literally right next to Tower 6's pirate ship pool, so you are going to get a lot of noise carried over from the Tower 6 pool.
Depending upon how quiet she needs it to be to nap, You might have some luck in the activity centers.... or maybe even just lounging on the couch and chairs in the lobby area.

Mid-day I definately would think that the main checkin lobby would be a much more relaxed (and quiet) area that the pools with all the kids playing around the area.
Also.... For the shuttle questions, unfortunately I can't help you there. I haven't visited the resort since the shuttles started charging, so I can't share any personal knowledge on how it works in practice. Someone who's visited since they started charging for the shuttles might be able to give you some information on how it works.... or you could call the resort and see if they might be able to answer the questoins for you.
Another option, if Push comes to shove, Would be to have the older kids take a Disney shuttle to a nearby Disney resort, Such as CBR, POP, or the Boardwalk. It might be easier to meet them (pick them up) from these resorts than it would be to get them from the park.