Do these stories claim to record historical events?
You are counting only the four canonized Gospels, three of which are mostly likely copied from the same source. There were many other Gospels written with much different accounts. For example, the "Gospel of Peter" claimed that Herod Antipas was the man who judged Jesus, not Caiaphas. Only the books that basically agreed were canonized.
How many copies of these exist in comparison to the writings of the New Testament? There was a consensus regarding legitimate apostolic writings from the earliest times, although a handful of false gospels were in circulation.
Paul supposedly lived in Jersualem when Jesus was welcomed by "multitudes" shouting "hosheanna," and yet he seemed to have no personal recollection of Jesus. How can that be?
He was an enemy of Jesus at the time. He became a Christian after the Resurrection.
Or a myth.
Josephus writes about Jesus, and his account conforms with the Gospel accounts. Is Josephus a myth too?
At this time there was a wise man who was called Jesus, and his conduct was good, and he was known to be virtuous. And many people from among the Jews and the other nations became his disciples. Pilate condemned him to be crucified and to die. And those who had become his disciples did not abandon their loyalty to him. They reported that he had appeared to them three days after his crucifixion, and that he was alive. Accordingly they believed that he was the Messiah, concerning whom the Prophets have recounted wonders.Another take on Josephus' account
What disciples? In the Gospels, Jesus had twelve apostles who followed him, but Pauls meets only Peter and John.
So?
I have a question. Does Paul ever meet anyone who knew Jesus in life, other than Peter, John and James? Do any of the thousands of people who met Jesus in life ever appear in the later books of the New Testament?
I don't know, I wasn't there. What difference would it make? Paul was concerned with handing on Christ's teaching.
The year of the crucifixion has to be theorized because the Gospel writers obviously did not know it. How is that possible?
Are you talking about the timing of the crucifixion in relation to Passover?
If you mean the Catholic Church, it is actually older than Christianity. Christ simply replaced the pagan gods that were worshipped on Vatican hill before.
The list of popes, dating back to Peter, is a historical fact.