The Road is likely a better book than NCFOM, but the film version of The Road is unlikely to be as good as the film version of NCFOM, IMO. The Road is too depressing, and the dialogue is not as interesting as NCFOM (which had a great sense of humor).
In any case, Blood Meridian is McCarthy's best book. Shame it's too bloody to ever be made into a major movie (although Ridley Scott is trying). Eg. babies hanging from trees, babies being smashed over rocks, donkeys being pushed off cliffs, puppies being thrown into creeks, raping, scalping - you know, the usual family fare. I guess you could tone all that down, but then you have an entirely different story.