1. No YK never showed any interest in HR.
2. He was trained since childhood by Qiu Chuji so had a solid foundation in orthodox martial arts. He also studied for an unspecified period under Mei Chaofeng, gaining the basics of Nine Yin White Bone Claw.
As to whether he could beat HR pre H7G, I seriously doubt it. Quanzhen martial arts takes decades to master and given YK's young age and impatience he was unlikely to have progressed very far in it. In addition neither of his martial teachers were very proficient in their respective arts so would have furthered hampered his progress. HR on the other hand had been trained by one of the Greats and although she may not have been very diligent her natural intelligent would have still given her the edge over YK.