Why January 1 falls on this and not on the next day of the year?

It's not even the beginning of the beginning of a new year( although this is also interesting - why year begins on this day, for example, used in Russia, and now in other countries, the new year starts at a different time of year.).The question is, why sometime it is this day of the year decided to take the first number.Why is this winter's day better than any other - winter, spring or autumn?

December 29, 2013 in Russia will be a work or a day off ?

On what day of the week it falls December 29, 2013 ?

2015 Winter Universiade years.What is the schedule of the competition ?

XXVII Winter Universiade .Granada, Spain .Which calendar starts ?