Ancestry review: Query about subscribing

I'm currently having my DNA analyzed. The results are expected in three weeks. Was just curious about my various nationalities, not necessarily inquiring about specific ancestors. I started a tree and the system is putting in maiden names of people on the wrong branch of the family. According to Ancestry, I have to fix that myself. In fact, everything involved with nailing down one's ancestry has to be done by the subscriber. Doesn't makes sense to have to pay for accessing a data base when the celebrities on "Finding Your Roots" don't have to do that. But then again, they probably pay about $10,000 to have their DNA analyzed and their ancestors revealed. Can anyone tell me if their regional DNA is specific or is it general? In other words, will one find the exact country they are from or is it listed as several countries in a region?