Call me paranoid, but tell me about viruses

If I did a search for viruses, I'd probably get 60 million hits. So I'm doing it the easy way--by posting.
It would be great if there were a list of the ways a computer can become infected by a virus or subject to spam. If there is, please let me know about it.
Every time I read about a virus or spam, I think about this.
For instance, I was reading an AP story on the net this morning about the new variant of Bagel. And it contained a couple of links to sites about viruses. And I wondered ... could I possibly get a virus or open myself to spam just by clicking the link and going to that site?
I used to think that the only way I could get a virus was by downloading from the net or by opening an e-mail attachment. Now I'm not so sure. And spam? Who knows?
You can see by my signature that I'm trying to protect myself. But I'm still worried.

 

Viruses change as computers change. Generally, there are a few methods of infection.

• Putting the file onto your PC and running it yourself (though a download, or a CD rom, or floppy)

• Downloading the file in an email or IM and it being run as a concequence of you opening the attachment or an exploit in the software

• Through a network exploit, such as a network service which has been compromised (e.g. the RPC exploit which resulted in Blaster and other varients, to which a patch was readily available by the way)

Probably the most scary is the network exploit. TBH you have to be a bit of an idiot to open an email with an executable attachment which seems completley irrelevant.

To help prevent network exploits, visit http://windowsupdate.microsoft.com/ regularly, and get a firewall.

 

Install one of these firewalls

Sygate- http://majorgeeks.com/download3356.html
Zone Alarm- http://majorgeeks.com/download388.html
Outpost- http://majorgeeks.com/download1056.html

and one of these Anti virus programs first before you go further

AVG http://www.majorgeeks.com/ download886.html
or
Avast download http://www.majorgeeks.com/download1968.html

All of these are free from MG. Then start reading about viruses.

FWIW I use Zone Alarm Free version and Avast. Bazza

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