Going into the reserves to fly just doesn't work like that. In order to fly in any branch of the military you need to be an officer. One of the requirements for that is a four year degree. If you go into the reserves you'll be working as a crew chief, loadmaster, or other job until you finish school. Then you have to hope you can get a flight slot upon finishing your degree. If money isn't an option, get through your ratings and start instructing as fast as you can. Going into the military could cost you quite a bit of time, especially if you get called to active duty.
Purdue is a great school, they have very nice facilities and equipment. It was on my short list but being from Missouri made it very expensive to attend. I believe that the only things you'll be required to pay for as an Indiana resident are your flight fees and books. Not a bad way to go.
Good luck!