exact permissible stay on a tourist visa and travel conditions during lunar new year

I received a 60-day tourist visa and will arrive in China on January 1. Is my first day counted from Jan. 1 or Jan 2? In other words, must I leave by March 1 or 2?

I understand Lunar New Year is on February 10. For what period of time will trains be maximally crowded?
One or two weeks before? One or two weeks after? Or even for one month?