It's a long walk from south of orangewood to DL. Not that bad in the morning, but on the way back it is rough. The ART is slow and a little hard to predict.
You may want to look at the small motels right across the street for you disney days, and then stay someplace nice with your points before or after.
Side note - If it is anything like it was in Sept. you need a plan to get to ride radiator springs racers without waiting in line for 2+ hours. Be at DCA when the doors open, and get in line for fast passes.