Over at http://www.techsupportalert.com/best-free-browser-protection-utility.htm there's a round-up of some of the best products available to help protect you when surfing online. One of the recommended products is from Returnil.
It works by virtualizing your operating system environment, which means that any files or data that get saved to your hard disk (or which get saved by viruses or malware) will automatically disappear next time you restart your PC. Therefore, any virus infection or malware/spyware/scumware won't survive the restart.
Until December 31st, you can get a free one-year licence for Returnil System Safe Pro. Just head to http://www.returnilvirtualsystem.com/productgiveaway and fill in your name and email address, and they'll send you a free licence code.