We just got back. Children who are under 10 must be accompanied by an adult on Shark Reef. (My DS is 8, and there were lots of kids MUCH younger. I know I saw at least one three year old kind of "riding" on his father's back. They have life vests available for kids who are not strong swimmers.)
We like both BB and TL. For children, I might be tempted to go to BB simply because there are two areas for kids. Tike's Peak is for the really little ones, and there's lots of play room. Ski Patrol Training Camp is spectacular for the slightly more adventurous. (There's lots that a 6-year-old would enjoy.)
TL is a lot shadier and prettier, but there's only one kids' area, and I wouldn't take a two year old near that wave pool! (The surf waves are frighteningly big!) On the other hand, the slides at TL are tamer and you could do a bunch of stuff besides the kids' areas with your 6 year old.
You'll love either. BB has less shade but more area for the 10 and under set. TL is gorgeous with tame slides, but the wave pool is not as kid-friendly. We have always gone to BB until this past time. DS loved TL, but he is now 8 and completely fearless!
Julie