PCTOOLS.COM

If your computer is sluggish, running slow, one possible reason is that it could be infected with malware such as viruses, spyware, or adware that is affecting its performance. One of the best friends that a computer can have is PC tools. This award winning software helps to remove viruses, spyware, and leaves your computer feeling squeaky clean, like it took a bath.

Among their suite of software that PC tools has available:

Spyware with Antivirus - removes viruses, adware and more.
Registry Mechanic - Helps to optimize computer performance by cleaning the computer's registry. The computer's registry holds all the computer configuration settings. Sometimes when software is installed and subsequently removed, the registry configuration may not be optimally cleaned. Registry Mechanic helps to restore and get rid of unimportant registry entries.
There are many more PC tools that help with firewall, file recovery and much more. PC Tools is a great investment to consider when you have a computer.