I studied the Jim Crow era, so this is a bit late for me. Check out: http://www.pbs.org/wnet/aaworld/timeline.html
1. Mostly Baptist.
2. Christian holidays... Christmas, Easter... Also New Year's, Thanksgiving, etc. Government holidays. There's debate about how widely and genuinely Kwanzaa was adopted. It's founder Maulana Karenga is a very polarizing figure. Middle class blacks were put off by his militant attitudes. And Juneteenth: http://www.juneteenth.com/
3. Typical Christian wedding. Not sure how prevalent "Jumping the Broom" was.
4. Same as everyone else, except there was a heightened sense of being aware of your surroundings and racial "vibes" to try to protect yourself from racial discrimination and violence. Racism was/is an omnipresent part of daily life for most (and not just in the South).
I. What religion were did they follow? The vast majority were/are protestant.
II. What were their holidays? Same as everyone else in the US except Kwanzaa began in 1966. Dr King day day didn't exist until the Regan Administration in 1983. It is a national holiday (everybody), not just African American.
III. What was their main form of wedding? Typical protestant ceremony.
IV. Brief of their daily lives. Everybody's life was, and is, different on a daily basis. I don't think you can describe a "typical" day for such a large segment of the population.
One of the driving forces behind slavery was religion. If you listen to the words of the old "spiritual" music written and sung by slaves, it contains many phrases like, "Swing down sweet chariot and let me ride," "Walk the streets of gold (in heaven) and "Pearly gates." They were led to believe that the more they suffered here on earth, the more they would be rewarded in the afterlife. It was those promises that got the slaves into religion that was far from what they knew in their homeland.