Travelling by Train to Sapporo

So I have visited Japan once before, exploring Tokyo and Kyoto. My desire is to explore the less-traveled parts of Japan, especially Hokkaido.

My original idea was to fly into Narita, spend a couple of days exploring Tokyo, and then take the train all the way up to Sapporo. Ideally, it would not be a shinkansen. What I would love to do is stop along the way and explore the towns or cities along the way.

My questions are: 1) would this two week vacation be enough to do the trip above, 2) what places along the way would you suggest exploring, and 3) is this plan a good idea (meaning are the places that we would stop worth it).

Any advice would be appreciated! Thank you!

Yes, you can easily fill two weeks travelling through Tohoku region. Both the east and west coast have great places to visit, and some of the central areas provide some less travelled places.

Heading up to Hokkaido you will need to ride a shinkansen for the Seikan Tunnel, but you could spend all of your two weeks there travelling around the island.

Plenty of places to see. Click the Tohoku section of this website. Id probably use shinkansen up to Sendai, then brach off on local trains from there to see the rural areas.

Go up on side of Tohoku and return down the other side. Go inland as required.

When?
How about hitchhiking?

I watched Japanese TV program in this month solo young UK woman traveler successed 6 days travel fr Tolyo to Furano in Hokkaido.
http://www.tv-tokyo.co.jp/youhananishini/backnumber/160912.html