A: Yes. Individuals with disabilities are just as interested in the company and its policies as anyone else.
A: Yes. You must give a precise description of the functions to be performed, the outputs expected, and the physical working environment. Only then can accommodations be discussed, should they be necessary.
A: No. This is not your concern. If your company offers some form of vanpool or other transportation services to all employees, you should ensure that it is accessible to individuals with disabilities and discuss it as you would with any other applicant. You may, however, ask the applicant if he or she has a valid driver's license only if driving a vehicle is included in the job description.
A: No. This is, frankly, none of your business and illegal.
A: No. It is only appropriate to ask if the individual can perform the functions of the job as they are stated in the job description. Emphasis on how the job functions would be performed may be elicited from the interviewee. This should lead to discussion about what, if any, accommodations he/she may need.
A: No. You can require a medical exam after a conditional offer of employment, but only if you require it of all individuals applying for the same type of position.