In 401 Mary was declared to have been the Virgin Mother. Since then all Catholic and Protestant churches have accepted this creed and these declarations. A little longer than the Muslim religion. The Koran has lasted over a 1000 year, even though many groups tried to destroy it. Again this does not mean the Bible is truth.
Faith is something someone has about something when there is no evidence for it.
Yes, as long as it is not imposed on others. Most Muslims are quite happy in their beliefs. Nowhere are there verses in the Bible that indicate one genealogy is for Joseph and the other is for Mary or that one was somehow meant for the gentiles. This is a myth on a myth - no biblical evidence. Just by looking at the table you can see there are some serious contradictions.