Insulation, Radiant and Vapor Barriers - Finishing basement

Here's the situation. I am finishing an office in the basement. I have 2x2s against the concrete. What would be the best way to insulate this? I have been told to glue insulation sheets to the wall between studs and have also been told to leave a gap between the wall and the insulation. What would be the best way to insulate? There is no poly between the studs and the concrete. I'm going to hang rock in a few days.
Thanks

If you have the 2X2 on the wall they should be P/T for sure. Id say glue some kind of polystyrene in there now is about all you can do.

ED

Thanks for the quick reply. I called the inspector and he said I didn't need p/t.
Thanks again

Boy you cant do it here . If wood touches cement it has to be P/T. Above or below grade

ED ;)

P.T. makes sense and the price won't kill anybody (I don't know about the preservative).

A code is a minimum standard and no more. In other words, it is usually initially the cheapest way to get a so-so solution.

Often is it cheaper and better to exceed the stadard because of the term value.