Insulation for Midwest

[Alex M.]

I have two newbie questions on insulation for ohio location in Erie County.

1) What do I need to know about ordering insulation rolls for walls? My property is gutted to studs, so I am assuming just need to know width in between studs, height of wall from bottom plate to top?

2) Walls are R-19 and attic R-30?

3) Are insulation rolls with vapor barriors the most ecomical way to go?

Thanks