In the ROTC application, it asks for the "home of record state" for myself and my parents; how is this different from the state I put as our address?
Some people have multiple homes. One of those is their 'home of record'. It's where they pay their income taxes, where they vote, etc. They might live in the 'second' home for most, if not all of the year, for some reason... maybe they are military and stationed temporarily at some base away from home, but the other home is their 'home of record'. However, the 'second' home would be their mailing address.
If you don't have multiple homes there is no difference.