What I have found is that the best way to pick the right size is to try several bikes and see what feels the best. With standover height, you want to make sure that you have 1/2 and inch to an inch between your crotch and the top tube. The seat tube length is what determines the size of the frame, and different bikes will fit differently even when they have the same seat tube length. the height of the bottom bracket will effect the standover height. The length of the cranks will effect how the frame fits you as well. I have a 58 cm Specialized Roubaix, a 61 cm Bianchi Strada, and a 63 cm (25 in) Schwinn Paramount, all of which fit me about the same way. I am about the 6'2" with roughly a 32" inseem as well. Your dad may want to get a bike with a longer seat tube and shorter top tube. Your lbs can fit you to a new bike and you can use those measurments when looking for a c&v. I still think what has worked for me is trying several different bikes.