You'll find crack-repair spray at hardware stores ... The key to patching torn drywall paper is to seal it first with an oil- or shellac-based sealer (KILZ Original and BIN are two brands).

If, however, you notice any other signs of settling—cracks in the foundation, torn drywall joints ... Working in paper-thin ...

You want the screw head to be 1/16 inch below the surface of the drywall paper. Drive it too far and you’ll tear the paper around the screw head, reducing the holding power of the screw.