The best way to prevent spyware and adware is to not get it in the first place. This means you have to know what you're doing and what you're clicking on. If you rely on prepurchased software to "keep you safe," you're setting yourself up for failure. Also, saying that Spybot and Adaware don't do anything for you unless you buy the full version is a fallacy.

Let's help the man get his computer working, not try to convert him to our personal ways of computing.