Yes, you can order an entire pizza. We have done it on two separate trips. The first time, I intended to do room delivery, but when I called, they told me it would be three hours! I decided to haul my tired self over to the dining hall. I don't recall how much it was, but it was a good deal (expensive compared to an entire pizza in the outside world, but a great deal to be able to feed my entire family for that amount at WDW).