It's the one with the Mayan temple-themed swimming pool. After a short discussion, TD and I determined that this will not count as a two-fer; visiting the Mayan temple ruins will remain on the list.
I went to B&N and read all the Disney World guidebooks one Sunday afternoon. I will share the best money-saving tip I found here: Buy your Disney merchandise at HOME. Here's what I do: watch sale papers for Disney-themed merchandise. Then, sneak to the store without your kids and hide the crap you buy under your bed. When it's time to go, pack one suitcase with "souvenirs." You can dole them out while on vacation, crumb-snatchers none the wiser. No need for them to know you didn't pay $30 for that 12" plush Minnie.