I do not have the expertise to be able to decide which parts to throw out.
neither do I. I do know that there were a whole slew of Gospels back in the day. The church (I am assuming the early Roman Church) edited down the Gospels to only those by the 4. I read there was a Gospel of Judas, if you can believe that.
I don't know what is the true bible. I believe Jesus is the messiah...I follow his moral teachings...after that I just don't know.