I have no idea about the route, but I would suggest Dallas to Jefferson.
JEfferson is a neat town with some nightlife and stuff to do.
According to Google maps, it's about 160 miles.
And when you get there, there are a couple of historic hotels that have great restauraunts.
http://stillwaterinn.com - great, great restauraunt.
Please let us know if someone comes up with a good route, as I'd like to do the same thing at some point.