Thanks for clarifyig.
Either will work. Now wasnt that a big help

But really. Preferred rooms cost more precisely because they are closest to the main building/dining/theme pool. So less walking. Not a factor for your group member on the
ECV.
I have mobility issues that require me to use a W/c in the parks (DH says its the only time that HE gets to push ME around


). However I'm ambulatory with a cane elsewhere. We check out the maps of whichever resort we're going to (we like the variety), go to the resort threads on the Resort forum etc.
But I'll try to spare you hours of searching. Basically, if you don't want a preferred room (I'm not prepared to pay the extra $ for this), then check out the maps for the Aruba and Jamaica buildings.
http://www.idhal.com/CBR/cbr.html
On our last visit there we were in bldg 51 which was connected by the bridge across the lake. I found it quite easy to walk to the food court in the morning. And at night the bus stop closest to our room was only a 1-2 minute walk.
The other building ,Jamaica 45, would be just as close.
You can make a request for either of these buildings, as well as a request for a ground floor room (because of the ECV-there are no elevators). Make your request by phone and let them know the request is for medical reasons. They won't guarantee them, but I've had my requests granted 3 times out of 4. Good luck