My hubby and I (and our 20 month old) will be on the Disney Dream on 9/7/11. The cruise ends on 9/11, a Thursday. We were thinking of possibly staying until Saturday to check out another Disney resort/location since we are in the area (from California). Has anyone done this and is it worth it? Any resort you would recommend over the other considering we have a young toddler?

You can't really go wrong with any Disney resort, it all just depends on what your looking for. Disney has three classifications of resorts. Value, Moderate, and Deluxe. The more you go up the more amenities that are included. However, even the value resorts are Disney quality with Disney service. The great thing about the value resorts are they are larger than life and are themed well for little kids.
Because you have a 20 month old a themed room "Nemo, Lion King, Little Mermaid, or Cars" at Disney's newest value resort Art of Animation could be great. If you just want to relax, enjoy the pools and hotel amenities maybe go up to deluxe or moderate. If you are going to hit the parks, then try to find a resort near the park or parks you frequent most. At Disney "TIME" is the hot commodity.
In my opinion for a quick fun packed, hit the parks, see as much as possible visit
.. stay at a value resort, save your money on the room for fun park activities.
For a little more laid back, some parks, a few resort activities, good themes, nice pools
. stay at a moderate resort. Port Orleans French Quarter is our favorite.
If you want to relax, take in all that is Disney with great pools that are more like water parks and amenities and activities that make it so you never want to leave the resort then stay at a deluxe. Animal Kingdom Jambo House is our favorite deluxe.
All in all I would say extending your vacation is defiantly worth it, we often hit Disney then catch the boat, but either way you are sure to have a magical vacation.