Anthony is correct.
DVC members staying on points can currently book DDP but it must be done in advance and for all guests staying in the villa for the entire length of stay. You will pay for it in full when you check into the resort.
You also mentioned DDE in your subject line. DDE is not available to DVC members, but only to Florida residents and AP holders. Since many DVC members use the great DVC discount to get AP's, they become eligible to purchase DDE that way.