Insulation, Radiant and Vapor Barriers - Insulating basement walls

My basement is warm in the winter because of the boiler and cool in the summer. The bedroom in the basement has paneling up with old insulation behind it.

I wanted to reframe the room with metal studs and use a poly board like one from Owens Corning on the wall and skip the R-13 between the studs.

I noticed some ants crawling from under one wall a couple of months ago. It seems they made a small home in the insulation.

Do I just use adhesive to put the poly board on the basement wall?
Should I still put up a plastic vapor barrier over the studss?

The basement will have a drop ceiling so the walls will be opened at the top.

Thanks,

Matty

This thread has been split from another regarding vapor retarder on basement walls. Doing so will provide greater opportunities for discussion on this topic.