I'm not sure, but I think you might want to focus on why he doesn't think God exists, and then try to prove he does, then move on to what religion is right. you seem to be going in circles with this kid. just my opinion. Very cool that you get to talk so much to him about this though.
and when you're talking about specific scriptures in the bible, quote them, or show them to him straight from the bible. don't just say, "the bible said the earth was a sphere", show/tell him what scripture its in. Then tell him how old that passage is. Then show him what encyclopedias said was the prevailing thought at the time that scripture was written. Remember, the Bible is the most powerful object you possess, and the most distinguishing trait of Jehovah's Witnesses, is our use of the scriptures.
Stef, this is very good advice, do what Dean says. I've got more advice coming to you, but I'm going to ezabel mail it to you. How exciting, you go girl!
Yeah . . . Thanks , I will keep this in mind! :)