Cynthia:
First of all, many thanks to your husband for serving our country and to you for his care.
When I took my father who is a paraplegic and in a wheelchair to Disney last year, I did a lot of
research beforehand like you are. It's a must for travelers with mobility disabilities. I applaud you for looking ahead, and can assure you that you and your husband will find Disney World to be one of the most mobility-friendly vacation destinations.
Your husband will not have to transfer to a Disney wheelchair but can enjoy the convenience and familiarity of his own chair. The designation of a ride requiring a guest with disabilities to "transfer to a standard wheelchair" is to denote attractions where an
ECV (Electric Conveyance Vehicles) or oversized wheelchair cannot fit. For example, your husband will be able to wheel right onto a special car for Buzz Lightyear, lock himself in place and enjoy the attraction. Scooters, which have larger footprints in many cases, would not work.
If you have any more mobility questions, feel free to come back and visit us!
Whitney