Eric, did you try creating a new, clean admin user profile in windows with a fresh install of CC? It would at least let you rule out software issues for the most part so you can diagnose. Often stuck registry issues, bad updates and accumulated junk codecs and software can be a big source of tricky problems. For whatever reason I can often troubleshoot these things from a fresh user profile, it's like resetting windows prefs. This still sounds like a hardware / software conflict problem of some kind. I would take a hard look at your drives and move your caches / footage to a new one and see if it helps.
And it is certainly possible only a fresh install of windows could be the solution. Can you test your footage / projects on any other system?
If you want to post your PC specs it would help a lot for diagnosis - be as detailed as possible.