Right my twopennies worth, having spent many months on the Tech Support Guy forums here http://forums.techguy.org/54-security/ my conclusion is, please do not be misled by all the hype surrounding the well known virus cleaners security or any other "well known" anti this or that, go to http://www.grisoft.com/doc/40/lng/ww and download AVG anti-virus, or better still go to download.com and get AVG anti-virus and AVG anti-spyware, both are free and are kept up to date. The problem with Mcafee, Norton, and all the other mainstream tools is they are nowhere near as up to date as AVG and all the lesser known ones.
Go here http://www.javacoolsoftware.com/spywareblaster.html and download spywareblaster, it will protect you by blocking installations of all activeX that spy/adaware use, another great free tool is Ccleaner here http://www.ccleaner.com/download/ it removes all your internet traces when closing your browser and keeps the registry clean.
Another must have is HijackThis which is an instant scanner and is handy when you need help, it instantly logs what is going on in your computer, DO NOT use HijackThis for anything more than preparing logs for "experts" to view unless you know what you are doing!