A secure democratic Net is a fundamental right

Secunia tested 300 exploits against the most popular antivirus suites. "While Symantec's Norton Internet Security 2009 took top honors, it detected only 64 out of 300 exploits, or just 21% of the total. Even so, that beat most rivals by substantial margins. Trend Micro's Internet Security 2008, for example, detected only 2.3% of the exploits, while McAfee's Internet Security Suite 2009 identified 2% and Microsoft's OneCare spotted just 1.8% of the exploits."

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You need other software for that. A firewall with application and exploit defense for starters or a HIDS. or just updated software in so far they are updates and in so far that the update process is easy.