Lots of options in regards to basic, scenic trails. Your best bet is to contact the forest service. They can provide you with the "new" map with designated areas for quads, bikes, Jeeps, hiking,,,,etc.
I've mostly ran the harder trails,,but I know there are LOTS of scenic, DD friendly trails. They are everywhere in the hills. But again, make sure to contact the forest service, as they will point you into the best (legal) areas to explore. Also, a GPS is handy here. I've found it easy to get lost.