It was few, roswel/UFOs, JFK, NWO, I believed most of them. Now what changed my mind is a intersting story. Sorry though if derails the thread somewhat. But, back in senior year of High School (2001-2002) *Note at the time I did not believe 9/11 was an inside job.
I had a great US Government teacher who knew about my obessions with CTs and would love to just debat with me about. They were always fun, and he then challenged me that if I could get enough information to convince him that there was something off about JFKs assanation he would give me an 'A' and let me skip class. Not wanting to waste an oppertunity like that I gladly accepted.
Over the course the next few months I read several books on the assantion, went to several websites and did a lot of digging. Here's where it just intersting, I decided to not just stick with the normal conspiracy throires sites and books. I went to every resource I could get my hands on. I mean to skip class the rest of the year and not get in trouble for it, I wanted to cover all my bases.
The more I researched it though, more the theories began to fall apart. Magic bullet was explained, the famous 'back and to the left' head movement, why over the years no one has said anything about it. (I found it during this our government can't keep long terms sercets, short-terms sure. Past a few months not so much.) the list went on.
Face with this new mountian of evidance I had to face facts. I was wrong, and when I would go back to the conspiracy books and sites and would not get any answers to counter this. Truth be told the feeling I got after this was wrong. So I went up to my teacher and told him that I couldn't prove it. I showed him all the information I had. From that day on I relized I need to take the time to look at all the information myself and not listen to just this one side and blinding agree with it. So my days of a CTer was at their end. And I haven't looked back.
As a side note, I got an A in the class, but was not allowed to skip the class.