Spybot - Search & Destroy is an anti-malware application designed for on-access and on-demand scanning and removal of various kinds of malware, including spyware, adware, hijackers and trojan horses.
AVG features most of the common functions available in modern anti-virus and Internet security programs, including periodic scans, scans of sent and received emails, the ability to “repair” some virus-infected files, and a “virus vault” in which infected files are held.
Malwarebytes' Anti-Malware is a high performance anti-malware application that thoroughly removes even the most advanced malware and spyware. With one of the fastest, most effective quick scans and malware removal capabilities on the market, this program is the perfect addition to your PC's defenses.
The Registry is a heart and soul of any Windows system. It contains information that controls how your Windows appears and how it behaves. After a long period, after installing and uninstalling a lot number of applications, your Windows registry will contain a large number of obsolete entries. These will significantly increase the registry size and thus will slowdown your computer, because Windows will need more time to load, search, and read data from registry. To keep your computer in top performance, it is recommended to periodically clean your Windows registry.