Driving Myoko to Matsumoto via Toyama

In January 2014, we (family of 2 adults and 2 teenagers) are hoping to hire a car in Myoko (after our ski trip) and drive to the historic villages of Shirakawa-go then to Matsumoto (or closer train station on way to Tokyo) over a two day period.
Do we need to hire a 4 wheel drive incase of snow conditions?
What kind of costs would be incur on the Toll roads?
Can we do it in two days? (350 kms in Australia is easy done).

Appreciate any positive or negative advice.

Do we need to hire a 4 wheel drive incase of snow conditions?

No, 4-wheel is not required, although some people will recommend it. Snow tires are required. Previous winter driveing experience highly recommended.

What kind of costs would be incur on the Toll roads?

Myoko-Shirakawago is about 5000 yen if you drive along the expressway along the Sea of Japan and Toyama (the fastest route). Shirakawago to Matsumoto is around 1550 yen for the expressway and toll tunnel through the mountains via Hirayu (the fastest route).

Can we do it in two days? (350 kms in Australia is easy done).

It is about a three hour drive from Myoko to Shirakawago. And about three hours from Shirakawago to Matsumoto. Could be longer if the weather is bad. Shirakawago-Matsumoto goes though high mountatains with winding roads and narrow tunnels. The region receives a lot of snow.

Time wise, the two drives will fit into a 48 hour period. Whether it is worth the effort is a different question.