hazelnut -- sound advice, without a doubt. I'm hopefully getting there . . . My OS is Windows 10 64-bit. It's an HP w/ i5 processor, 8 GB Ram, 919 GB HD with 142 GB currently used. Bought it over 5 years ago (ouch!).
Andavari -- Turns out I has System Restore "ON" but didn't have any space allocated for it -- hence no Restore Point existed.. I moved the slider to 6% (55.14 GB) and manually created a System Restore Point. Then I went back into CCleaner / Tools / System Restore, and Voila! there it was, no problem.
Onward. What else do I need to know before I do a Registry clean? I'll back up all my documents, music and pictures to my portable HD of course. Not sure if I should (or could ?) back up my whole system that way or not . . . Would that be feasible?
Anyway, thanks to you both for replying.