We flew into Orlando-Sanford last November. It's a small airport. We didn't have any problems. We rented a car before we went down, so our car was ready when we got there.
One piece of advice, we took the main highway to Disney from the airport, is it I-4? Traffic was awful. When we left Disney and went back to the airport, the cast member gave us an alternate route on a toll road. There wasn't much traffic at all. It was a much better commute, so you might want to take that into consideration if you decide to fly into Sanford.