We love the Beach Club Villas, which are within easy walking distance of Epcot (one of our favorite parks) and the Boardwalk. Via Epcot, you can catch the monorail to Magic Kingdom. And you can get a boat to the Studios from a short pier just outside of the BCV. (Of course, you can get buses to anywhere too!)
We've never had any trouble booking the BCV, even though we own at Bay Tower (which we've never stayed in yet). But we've also never tried to book over such a popular time period.
Bob