The newest version gives you options as to overwrites. Also keystrokes are not automatically collected typically without a keystroke logger. I would go through and delete files, folders, and uninstall programs as necessary and then uninstall explorer and chrome or whatever your browsers are, then run ccleaner with 35 pass (gutman) overwrite. Uninstalling your browsers releases the sectors they used to collect data and then the overwrite removes all data there.
Here is some info on whether the info can be recovered:
The National Bureau of Economic Research criticized Gutmann's claim that intelligence agencies are likely to be able to read overwritten data.[3] There is yet no published evidence as to intelligence agencies' ability to recover files whose sectors have been overwritten, although published Government security procedures clearly consider an overwritten disk to still be sensitive.[4]
Companies specializing in recovery of damaged media (e.g., media damaged by fire, water or otherwise) cannot recover completely overwritten files. No private data recovery company currently claims that it can reconstruct completely overwritten data.
https://en.wikipedia.org/wiki/Gutmann_method
I have given away a few computers and used this method and am confident that it has removed my personal info. Just my 2 cents.