I started out with a smaller group, the "Friend & Workers", a.k.a. "Two-by-Twos". When I got to be 12-13, I started playing chess and discussing what I knew of the Bible over chess games. During my teenage years, I also tried out a little Karate (a few weeks), some "Dungeons & Dragons" (a year or so), some community band (perhaps 3 years). By the time I hit 20, I had decided against taking in blood transfusions, stopped celebrating my birthday (due to some gifts showing total disrespect for my values and tastes), and stopped celebrating Christmas (from my reading of personal encyclopedia articles on the origins of it).
I was in my early 20s when I answered the door for the first time to JWs myself. I was glad to learn about a religion that disfellowhipped people for adultery. Field service gave me the opportunity to have quite a number of active discussions with people of varying religions, and even several with some that had biker gang affiliations.
Since then, I've played pool/ billiards and done family history by e-mail, and have often got involved in Bible topics in those way, too. JWN, like all these other methods, exposes me to both some of my strengths and some of my weaknesses, which gives me all the more reason to take notes when I attend WT programs, read WT publications, and do look-ups in my Bibles and Concordances.