bsmt wall insulation

Hey,
I live in Saskatchewan, Canada and we have an uninsulated concrete bsmt. I was planning on just putting up 2x4 walls to conserve space. I've heard most heat is lost through bsmt so wondering if 2x4 walls are enough for bsmt and also what type of insulation is recommended batt or foam board? Also should studs be treated? or just bottom plate? do I put plastic under the bottom plate? what is the recommended way of fastening walls to floor?
thanks