I guess that these two groups are part of junky families.
Hillbillies live in the far in the country especially deep woods, and perhaps they are friendly.
Rednecks set up their Confederate Flag in the public, and some are racists.
I would say Jeff is the wrong one to be asked to define between hillbillies/rednecks. He and his family lives in a very affluent suburb in Atlanta's northern suburbs, where all the rich yanks live.