There are a number of scams like that. MyCleanPC is another one. I would never go near them.
Here is all you need...
The following are all good
free tools for keeping the computer clean and free of malicious code as well as other nasty stuff.
CCleaner
Malwarebytes Anti-Malware
Revo Uninstaller
Avast! Antivirus
Zone Alarm Firewall
These are what I have been using for years. With these tools I have never had any malicious code cripple or otherwise have any effect on my Windows system. Also, the database updates for Avast! and Malwarebytes are free as well.