I can give you a few answers. Bonnet Creek is closer because you actually have to drive onsite to get to it, however, it's not much further.
My personal preference is Bonnet Creek. It's newer, gated, and very, very nice. I have attended a couple of conferences at the Caribe and had reservations there once, but I've heard some complaints here and there about it so I wound up canceling my reservation. The property looks to be very well maintained, and it has a gorgeous pool, but it can't hold a candle to BC in my opinion.
I know that BC does have regular transportation to Disney. We didn't use it, but I did see the bus several times.
Hope this helps a little bit!
