I've been studying Christianity and the Bible at university for some time and all I can say is it can't be explained quickly in one post, so I won't even try. The more I learn about it, the more astonished I am at how much I didn't know. It's quite embarrassing to think I used to go door to door, feeling oh-so-smug about my wealth of Bible knowledge. I knew very little then and what I did know was wrong.
I've watched quite a lot of the History Channel's religion programming and I've found it to be biased and misleading. I guess the scholar in me wants a certain amount of objectivity.
Remember at Pentecost how, after Jesus' death he sent the Holy Spirit to guide the early Church? Remember that Jesus said to Peter that the gates of hell would not prevail against his Church and that he would be with it always? We really believe that. We believe that Jesus really did send the Holy Spirit at Pentecost and that He has really guided his Church and never abandoned it. After a couple of hundred years of discussion, the Catholic Church weighed the authenticity and authorship of the various books floating around and decided which ones were in keeping with the teachings of Christ and which were not. The ones that were in keeping were codified into the Canon of scripture that we have now. Even the JWs haven't tried to introduce new books into the Bible or rejected the Bible, which was given to the world by the Catholic Church.
I don't believe in a man made religion unless that man is Jesus. I do believe in Jesus. I didn't for a long time. I was so burnt out after 25 years as a JW that I didn't believe in anything for the longest time but that has changed with time, research, and experience.
If you want to go back and research the history of the very, very early Church, from the time of the apostles through the first 300 years, read the writings of the Ante-Nicene fathers. There is a 10 or 11 volume set of their writings still in print. There's also a good book that puts some of the stories of the early fathers in a very readable form, called "The Four Witnesses" by Rod Bennett.
They say women come to religion through their hearts and that men come to religion through their heads. With me, it was a combination of both because my heart had been bloodied and beaten by the WTBTS.