During our stay in July, this is the route we (and quite a few others) took each morning:
Although we were in building 27, we walked back to the bridge across from the Hospitality House and began there.
Head back toward building 27 along Peninsular Road.
Stay on Peninsular Road until it ends. You will be looking at a bus stop between buildings 53(on you left) and 52(on your right).
Make a left and pass buildings 53, 54, 55, and 56. At the end of the parkin lot, make a left.
Stay off of the cart golf path. You should now be running parallel to the water way. This will take you into DTD/West Side. Keep the water on your left. You'll pass Cirque Du Soleil, House of Blues, Wolfgang Puck's, and Bongos all on your right. Go until you can go no further. Turn anround and retrace your path.
My son beleives its about 2 miles one way.
Hope that helps.