Youd be taking a pretty big risk buying into either one right now. Eth is just waiting to get dumped but if u had to buy one then i think  the hard fork is the one to choose since it has the highest value but that could soon change. They probably shouldnt have forked in the first place so classic is the one that is the original but like above poster says that could be abandoned completely. Investing in either could potentially be you throwing your money away.