There is no "drop-off" actaully close to the entrances. First of all, at MK (other than using the Disney buses) youhave to go through the TTC, and it is quite a hike from both the drop-off and medical parking. At AK it is definitely a hike from both the trams and medical parking. At EC the trams are in closer than medical parking, but it is still quite a ways. And at the Studio there is again a very long distnce from ttrams/buses/medical parking to the entrance.
At all three parks there are "borrowable" wheelchairs which can be taken from medical parking to the gate (and back), but these cannot be taken in to the parks and often they are all at the other end (such as in the morning they may not have yet ben returned to the parking lot.
I have two recommendations. The firs tis contaqct your state Motor Vehicle department to get a handicap placard for your MIL (unless she already has one). Even if she does not drive she can get one. Normally there is a form you can download at the DMV website which can be filled in by her doctor.
The other is rent either a wheelchair or
ECV from an off-site comapny. This way you will have it with you. Below is a listing of some of the companies which do rentals, as well as some additional informaiton which might help.
Here are the urls and phone numbers:
Walker Mobility:
888-726-6837
www.walkermobility.com
Care Medical:
http://www.caremedicalequipment.com/
407-856-2273, Toll Free U.S and Canada (800) 741-2282
Randy'S Mobility is in Kissimmee
http://randysmobility.com
407-892-4777
Colonial Medical
http://www.colonialmed.com/about_cms.html
800-747-0246
ScootAround
http://www.scootaround.com
Toll-free, US and Canada 888-441-7575
I have used Walker a few times. They will ask for a credit card and charge it the day before arrival. They will deliver the ECV to your hotel bell services before your arrival and pick it up there after your departure. Their rates, especially for longer than a week, are much better than Disney's. Also, their scooters are much better.
You don't say if you are using a car or what. If you are using a car for getting around, the
ECVs break down into five pieces, the heaviest about 39 pounds. They take about a minute or so to take apart and about two minutes (once you are used to it) to put it together. You will need a full-size, four-door sedan or larger to have sufficient trunk space.