If you are truly disabled you will want to honestly assess your physical ability. Food service requires long hours standing on hard floors. The commercial kitchen is a hot, greasy environment that usually is loaded with stress. Hiring staff usually creates as many issues as it solves. For example just recently our night cook on duty forgot to run pork the night before we had 80lbs to deliver for lunch the next day. Yeah, big fun.
If you have not worked in food service before, I HIGHLY recommend that you do so before you invest a bunch of money or quit your day job. Find an existing restaurant or catering outfit and go to work there for a couple months - offer to do it for free if you must. (Doesn't have to be a BBQ place) You will learn a ton about the realities of the business. This will either reassure you that you can do it better or tear down the romantic visions of "having a restaurant" that lead so many to invest their savings into a business that fails in the couple years.