Hi Michelle,
There are no handicapped discounts available at Walt Disney World. Even a guest who does not participate in any of the rides would still have lots to do at the parks with all the parades, shows and fireworks. However, I wouldn't be so quick to dismiss your mother's ability to take part in the attractions. There are many very gentle rides at Walt Disney World that are popular with seniors. For example at the Magic Kingdom, It's a Small World, the Jungle Cruise, Country Bear Jamboree, Carousel of Progress, the People Mover, the Hall of Presidents, and others involve nothing more then sitting - with no drops, bumps, jolts or other taxing situations. You will obviously need to consult with your mother's doctor about what is appropriate for her, but my guess is that there will be much more that she can do than she can't.
If you'd like more information on the attractions, click
HERE on the Disney website. This page includes links to documentation about navigating the parks with disabilities.
Another great resource is a book
called "PassPorter's Open Mouse for WaltDisney World and the Disney
Cruise Line." This sells for approximately $20 and is available through
amazon.com and many larger bookstores. Open Mouse gives incredibly
detailed information for Disney guests with any sort of challenge, from
anxiety to allergies and everything inbetween, including heart conditions,
If you get this book before your trip, you'll be able get your plan
together in advance of your arrival so you'll be completely prepared to
have a great vacation.