CCleaner

Optimize your PC performance by fix the registry value of your PC, sometimes we make mistake running the pc with unsave software. virus, spyware, adware,worm also can make our PC running slow and very disturbing. CCleaner is system optimization utility, privacy and cleaning tool.

It removes unused files from your system - allowing Windows to run faster and freeing up valuable hard disk space. It also cleans traces of your online activities such as your Internet history. Additionally it contains a fully featured registry cleaner. But the best part is that it's fast (normally taking less than a second to run) and contains NO Spyware or Adware.this is a freeware

Advanced features to remove unused and old entries, including File Extensions, ActiveX Controls, ClassIDs, ProgIDs, Uninstallers, Shared DLLs, Fonts, Help Files, Application Paths, Icons, Invalid Shortcuts and more... also comes with a comprehensive backup feature.

Website to download : http://www.piriform.com/ccleaner