route to Tokyo, Kyoto, Osaka, and Hokkaido

I'm planning to visit Japan at December and I want to know the best and cheapest travel route to Tokyo, Kyoto, Osaka, and Hokkaido for 2 weeks, and also I was wondering is there any kind of place that I must visit at December in those locations?

If you are arriving and departing from the same airport, then I think it's worth buy a 2-wk JR Pass.

Not sure if it is the best for you, but the Seishun Jyu Hachi Kippu is definitely the cheapest...worth looking into anyway...

thanks for all your help! I'm sorry I forgot to mention that we intended to transport from Tokyo-kyoto and Tokyo/kyoto-hokkaido using planes, so what I really meant to ask was when should I go from one city to another, like, "after Tokyo you should visit Kyoto first, then you go to Hokkaido". I will visit Japan at late December until early January, so I was wondering when is the perfect dates to visit each of those cities. I'm sorry that I didn't make my question clear.

another thing I forgot to mention, Tokyo will be my starting point.