Japan - Feb. 26th to Mar. 16th - Where to go?

I am going to Japan from end of Febuary to mid March... But where to go? I would like to see a lot of beautifull winter scenery but most national parkes and the like seems to be closed at this time because of too much snow...
Does anyone know of any places that are perfect to go see mountains and iced forests at this time a year?
I like Hiking and I can speak some japanese so I do not mind if the places are a littele hard to get to if just they are beuatifull :)

I would like to see a lot of beautifull winter scenery but most national parkes and the like seems to be closed at this time because of too much snow...

No, they are not closed. Hiking trails are naturally closed, but the winter can be enjoyed in other ways, such as skiing, snowboarding, nordic skiing, snow walking, etc.

The best areas to see winter scenery are Hokkaido, the Tohoku region and the higher elevations around Nagano, Gunma and Niigata.

Iced forests are particularly famous in Zao Onsen, Yamagata Prefecture and Hakkoda Mountain in Aomori Prefecture:
http://www.japan-guide.com/e/e7927.html

There's a train that runs between Kakunodate and Takanosu which offers beautiful winter scenery. We took that trip late February this year.
http://www.akitajet.com/wiki/index.php?title=Akita_Nairiku_Line

Zao Onsen's snow monsters are illuminated until early March.

I'd also suggest Yamadera, Nyuto Onsen, Yamanouchi (snow monkeys), Takayama/Shirakawago.