I don't know what your preference is, but Ochang is going to be very very small. It's not terribly far from the southern most suburbs of Seoul though. You will probably need to learn to read Korean quickly as you will need to take the bus everywhere. If you are lucky you can take a bus from your area to Cheongju and transfer to a bus that takes you to a bugger town.
Small town living in Korea is not like it is in the West. You will most likely have very limited access to groceries, and may need to travel for a while to find a supermarket. Imported products will be unavailable there. There also will most likely be no other westerners in the area for quite a distance. If that all appeals to you, then you hit the jackpot. If you feel uncomfortable about any of it, I would suggest a larger city.