If you are getting a handicapped accessible cabin you will not have a choice of loop. Sorry but they are all in the same loop. Unless the added and moved them into 2 loops they will be in loop 2800 which is where they were as handicapped homes.
If you are getting a standard cabin then loops 2400, 2500 and 2600 are closet to the pool and laundry area. You will need a golf cart or the bus to get to the Meadows and Pioneer Hall areas where the other activities are located.
Check over on the Disabilities Board for tips on handling WDW with a child with limited mobility.
Pooh