Malwarebytes Anti Malware is a free anti malware removal program that targets the kinds of malware most anti virus suites don't try to target. I highly recommend it. It has fantastic ratings and reviews everywhere you go. It is not an ACTIVE protection suite, meaning that it does not constantly run in the background, only when you run it.
Spybot Search and Destroy is a great preventative program that uses prevention methods to stop spyware and adware from getting in your computer and changing settings. It also has a scan and removal tool for known spyware threats and tracking cookies.
Between your antivirus, Spybot Search and Destroy, and Malwarebytes Anti Malware you should have pretty much everything you need to stay malware and virus free so long as you maintain smart browsing and downloading habits.
If you're really interested in keeping your PC protected and understanding what an an on-access (antivirus suite) and on-demand (Malwarebytes Anti Malware) do read this very helpful article:
http://lifehacker.com/the-difference-between-antivirus-and-anti-malware-and-1176942277
If you're interested in knowing how your Kaspersky Antivirus stacks up against the competition (right now it is the top rated paid antivirus) you can view this article here:
http://lifehacker.com/5865356/the-best-antivirus-app-for-windows That article is a little more subjective than the previous one so take everything with a grain of salt. However, they do use an independent and fact-based website to get protection benchmarks which you can find here (copy paste the link because hyperlinking it isn't working properly):
http://www.av-test.org/en/home/?avtest[type]=3&avtest[platforms]=5-4-1,9-8-6&avtest[series]=9-8-6:1398902400.1,10-7:1396310400.2,5-4-1:1391252400.2/sepoct-2012/
