If you are flying to Orlando, and you don't have an Annual Pass, you might well find that if you compare a Value stay vs. an offsite hotel + rental car + daily theme park parking that the hotel has to be pretty inexpensive to beat the Value room cost. And, you really don't want to stay offsite without a car---it's just too frustrating and inconvenient to rely on hotel shuttles for the most part. There are a few exceptions (Bonnet Creek, the Downtown Disney resorts), but they are probably not so much less expensive that it is worth it for a couple.
On the other hand, if you are driving down, then the equation changes significantly, and offsite would be a more attractive proposition for an adult couple. In that case, the Priceline model is probably a good way to go.
If you are squeezing to make this trip, there are other easy ways to keep the costs down: avoid most table-service meals, skip the hoppers, etc.