Shifting to Japan

I am an Indian living near New Delhi. I have an offer to join an MNC in Nagasaki, Japan.
I am married & have 2 children ( 7 yrs/ 3 yrs)
I am not able to take decision due to various factors.
1. Cost of Normal living in Japan ( Monthly expenses for a normal family in $US)
2. Nearby English medium school , nearest to Nagasaki Town.
3.About other problems that I can face.
4. Cost of Visa for my wife & children
Can anybody help me with urgent attention. I am need of great help to take a decision.

1. Cost of Normal living in Japan
Depends on your lifestyle and arrangement of your company. Housing rents in Nagasaki are more reasonable than those in Tokyo. You may rent 3-rooms apartment for 950USD/month.
http://yachin.homes.co.jp/city/ad11=42/

Other costs
http://www.japan-guide.com/e/e2202.html

2. Nearby English medium school
There'r American schools in Sasebo. Not sure if they accept Indian students, though.
http://www.kyushu.meti.go.jp/invest/more/mor_livin1.htm

4. Cost of Visa for my wife & children
Check Japanse Embassy in India. But, I don't think this is a big problem as fas as your employers provide necessary documents.
http://www.mofa.go.jp/j_info/visit/visa/index.html