The crawlspace is 21' x 11' located behind my garage. I plan on removing the gravel and installing a new vapor barrier, then run 2x4 floor joists and plywood floor. I also plan on insulating the walls and floor.

Questions
1-should I use a 10 mil plasic sheeting as the vapor barrier or should i use something like tyvek?
2-I was planning on using r-19 on the new floor and rigid insulation on walls. Is this correct?
3-do I need insulation in the joist above to solve the cold wood floors?

Additional info...
our basement is not finished but has carpet and a gas ventless heater that we heat the basement with.

I have large overhangs 18" deep all around house a mild slop away from the house outside and my sump pump never runs (1 per month). we have had no water issues which is really good with the amount of rain we have had and listening to the neighbor's sump pump running all the time.

Foam board insulation (EPS, XPS) can go on the floor and walls in accordance with US Dept. of Energy recommendations for your climate. But no insulation should be installed on the crawl space ceiling. Air supply to the crawl space depends on the details of construction and any radon mitigation system that may be used.

I would not build wood floors unless you were to pour a new concrete floor.