Painting - Patching wall after wallpaper removal

I recently removed the vinyl wallpaper in the two bedrooms of my new home. The paper came off with relative ease but there is some sort of thick cardboard like covering on the wall between the drywall and where the wallpaper was. It's got a very strange texture and in some places there are holes where it came off with the paper. I'm pretty sure that if there were no holes I could just seal the surface and paint over it but I'm not sure what to do about the holes. Do I sand and patch them? And if so with what? Or, do i just try to remove the whatever it is and get down to the drywall?

Site unseen, this is a difficult one. Do you think you would be happy with the results if the said "board" was patched and painted? How easy would it be to remove, would it tear up the rock? Are there seams in the board?

I do not know about this covering you are reffering to, but you could try to patch it with joint compound, be aware it may take 2 or 3 coats, don't try to build it up, but apply and wipe smooth with the wall, repeat when completely dry. You could try that and see how it looks.

The texture you spoke of, is it a texture you could possibly match with some joint compound thinned to a "thicker than paint" consistancy and dabbing small amounts with a brush?

It is so hard to tell without seeing it, you may want to get a profesional in your area to look at it, then again, someone here may know exactly what you are talking about.

Could it be the backing on strippable wallpaper? If it is use some wallpaper remover and it should come off.