Avast cleanup

Every time I go via the SPEED UP route and try to put to sleep the offending programmes, the computer appears to be doing what I’ve asked, but goes no further. The “busy” wheels continue to whirr and, eventually, I have to force a computer shutdown, as no other normal procedure to halt the programme or shut it down works. I’m using Windows 10 with Firefox as the browser. I do have the latest version of Cleanup