I had natural wood paneling in my sunroom and could not stand how it looked. So I lightly sanded the paneling, primed the walls and painted. (Don't try to skip priming the walls: this extra step will provide the proper base between the paneling and your chosen paint color. Without the primer the paint could easily peel off the paneling). The resulting look is reminiscent of old fashioned bead-n-board. It looks wonderful. Also, I added a chair rail around the room and walled papered by bottom half of the room with a lovely vine and leaf pattern paper. Painting the room really opened it up and made it a very welcoming space.
FYI. if the grooves are really deep you can always fill them with wood putty to even out the wall prior to painting. ... View related article.
