Using Windows XP is a risk. Win 7 costs only 40 $, so I don't understand that...
Sorry for the delay.
As far as my knowledge goes and from what I have read or seen from others.
I think that 9 out of 10 security risks or getting infected is because users ignore basic rules for safe computing or don't know these rules.
(Probably up to 99% of infections require user interaction.)
Just a few to mention :
-blindly plugging in an USB stick.
-automatically clicking on a link of email or sites.
-disable "show file extension", default by Win enabled, stupid idea of MicroSuck.
Then we can add I guess that most infections seem to come from buggy browsers.
Exploits being exploited.
-Java, I have given up on the never ending list of security fixes.
(I really dislike Java, I only installed it for NEM and some other projects.)
-default setting's in all my browsers, indeed Java disabled
-.NET same story, not installed on my PC's, besides from being big time bloat ware.
Installing 100's of Meg just to run a simple app, that really sucks.
-Flash.
And a bunch more of buggy software, most inet related apps.
WinXp I would say is the least to worry about I think.
Support for consumers has been terminated, but it still continues for large company's, as long as they are willing to pay for it.
Support for embedded however will continue for some years to come.
Thanks to this great project, unofficial SP4, I guess I can safely add many more years to come :
http://www.ryanvm.net/forum/viewtopic.php?t=10321&postdays=0&postorder=asc&highlight=sp4&start=0
I do have virus scanners installed (2) but disabled real-time monitoring.
Scan on demand as such, and not when ever I click my mouse.
Preventing endless/useless scanning.
Maybe shocking for some, but on average I only do 1X-2X a year a virus scan of my PC.
And then Win directory only.
Exceptions are if I download a file using p2p or other untrusted sources.
Then I upload to www.virustotal.com, a long list of scanners testing your file.
In some 15 years of using windows, I only got 2 infections of my PC.
Reason, I wanted to see what happened if my PC got infected and if I could clean up the mess.
So I willingly run a virus for testing, my system went bananas, launching process endlessly. killed 1 and many more appeared.
Was fun, and I managed to kill it in the end.
The other was a browser hijack, homepage getting screwed up, fixed problem but it was back after re-boot.
They used a simple bat file to merge data back to registry during boot.
Easy to fix when.
Of course I could have ended up with a real and nasty virus, flash and bye bye bios, or ending up with a root kit.
In both cases I would have been screwed, big time.
A mobo bricked is no fun, same as a nasty root kit.
On a side note :
If I would upgrade it would cost 40 $ plus a new PC, so a couple of 100's $ (? )
Running old software on new hardware usually gives you a big performance boost.
And yes I am a bit weird I guess. ;D