If you are flying into MCO, and looking for the absolute bottom-dollar cost, it's often the case that a Value room is less expensive by a few dollars once you throw in rental car, and theme park parking. As a concrete example, I have an upcoming stay for 2/25-3/3. That week in a Value resort, under the current room-only promotion, would cost $742.
So, for your family, it would be about $1500 total for lodging and transportation. But, that's to put yourselves into two 260 sq. ft. boxes with double beds. For maybe a few dollars more, you could have twice as much space, private sleeping rooms for each couple (in larger beds), another private room for the kids, a third bathroom, plus lots of other amenities (kitchen, washer/dryer, etc.), plus throw in the van (or maybe two cars) and theme park parking (for one or two vehicles).
Ultimately, when it comes to WDW lodging, there are three things you might want:
1: To be onsite.
2: To have a reasonable amount of space.
3: To spend a reasonable amount of money.
In general, you can have two of those three, but most people can't get all three at the same time. So, you have to decide which of these you are willing to live without, and which is most important to you.