Setup:
CCleaner was suggested for use on another forum and it sounds good so I'm quite interested...
But I try and be careful before adding any new software on my PC and competition between scecurity and utilities software creators seems to be keen.
I also worry about duplication of servides or features... having two programs installed... each trying to do the same thing... like Windows Firewall and Zone Alarm... for instance.
The first thing I do on a new PC is install Zone Alarm Free, turn off Windows Firewall (just bacaues I know ZA from prior usage) and then install AVG Free.