The best recommendation I can make is to do a LOT of research before buying, and not just read the Disney marketing materials. Not that the marketing is misleading, it just doesn't tell you how
DVC works, and what the timeshare ownership experience is like - very, very different from reserving hotel rooms. You'll want to be sure that DVC fits with the way your family vacations, and run the numbers to make sure it's a good value for YOU.
One of the very best sources for that info is the DISboards. I read these boards like crazy when I was deciding whether or not to buy, and it was invaluable. I knew a LOT about DVC before I signed the contract, just by reading about real world experiences and explanations from long time members, and I'm a happy DVC owner now because I knew exactly what I'd be getting.