Firstly, Jerome, that was WAY too many topics for just one hour! JW's always have a ready made answer for someone new. They get a lot of this "training" from their weekly service meeting. A "text" they like using is called "Reasoning from the Scriptures". Ask your girlfriend for a copy. It will help you prepare yourself for their "standard" replys.
I studied with a JW for months trying to make an inpact, but all it got me was a "stopped study - for MY own good" - guess they thought that I was better off NOT knowing the "TRUTH"(tm), then knowing it and rejecting it.
Don't give up - just go a bit slower. Stick to ONE topic each session.
As for talking to your girlfriend's parents - I'd go REALLY slow with them. And DON'T tell them you will NEVER become a JW. They will force your girlfriend to cut off all ties with you.
BTW - how old is your girlfriend?
NewLight2