I don't have your situation and I really didn't use scriptures when talking with JW family, except to say that I should be examining the doctrine for myself as the Bereans did.
I suggest taking a hard look at jwfacts.com to aid you in talking to your folks.
Three great areas for preparing yourself are
1. 15 minute guide to truth: http://www.jwfacts.com/watchtower/15-minute-guide-to-truth.php
2. Is it Truth? : http://www.jwfacts.com/watchtower/truth.php
3. Fear and Mind Control: http://www.jwfacts.com/watchtower/fear-cult-mind-control.php
Try not to say "mind control" this early with your discussion, but talk about the fear of questioning anything they say.