I glued a 2" extruded foam layer on the wall and also attached it with furring strips and glued another layer on top of that, with grooves dadoed into them so they were flush. I'm just now getting along with screwing densarmor drywall to the furring strips. Electric wires were put in grooves that were routed in the surface of the first layer. I also put multiple layers of xps foam in the rim joist area - that and the dadoing were a pain. Screwing the drywall to the furring strips is turning out to be remarkably easy (sans any finishing though). The areas where stuff is next to or attached to the concrete are annoying - water softener, well water filter manifold, pipe for boiler, breaker box, oil tank, etc. There's fiberglass in the joist area overhead, so the plan is to cover and contain it with landscape fabric. I thought about covering with drywall, but I'd have to do some boxing in, which wouldn't be bad I guess, but I know I'd have to get up there periodically-I can always add it if I don't like the fabric. I also don't think I'll make a boiler room, since who knows, maybe there'll be a pellet boiler there one day.
Still don't know what to do with the floor -.tile, paint?
Sorry for the extensive hijack, but I'm still working (slowly) on it and it does help keep the heat in.