Some advice from the pro's now
AVG is the computing equivalent of the chocolate fireguard, it stops windows moaning about not having any Antivirus but thats about it.
Also within the current version of AVG it has a nasty habit of redirecting all your web traffic through AVG, and while you said you do nothing dodgy, this can have a detrimental effect on your browsing speed.
So free options you can look at for AV protection are [url=http://www.avast.com/eng/download-avast-home.htmlAvast[/url as someone already mention is good, but can be a little resource hungry on your PC.
A better option would be [url=http://www.free-av.com/en/download/1/avira_antivir_personal__free_antivirus.htmlAvira[/url. This rates very highly in most virus protection reviews and outperforms most paid for products, its my personal choice of AV.
Spybot as suggested by Rob is excellent for keeping all the nasties that aint viruses away.
If you are using router you have no need for a firewall on your desktop PC, tho if you are using an ADSL USB modem, or one of those Mobile Broadband dongle things then you will need a firewall.
If anyone wants anymore PC advice just ask
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