Woo! Win2k FTW

*ducks*
But yeah, this is the reason why we vet updates before we let them through; I stopped relying on Windows updates to protect systems a looong time ago. This hype about keeping the system up to date being absolutely essential? It is propaganda meant for people that don't know better.
It doesn't apply to people like us who have been using computers since the Win3.1 days and never been infected because we have brains and don't do stupid things.
It is meant for people that open .zip and .txt.exe attachments and browse the web without adblockers and blacklisting/filtering software.
The hard truth is that a fully up to date system is just as easily infected by malware and crap as a brand new system. The problem isn't the OS, it is the user. Always has been, always will be.
It's much more worthwhile to invest in some decent defense tools; a decent anti-virus (Although picking them out is hard these days; Norton and McAfee are out. AVG is a lot worse than it used to be. MSE seems popular and isn't too resource hungry but really murders disk transfers involving exe's and is no good for 0-day stuff. At work we use Sophos which has saved us many times from user idiocy but it's expensive) and/or anti-malware (malwarebytes' one is worth the small fee imho!).
Filtering at network or browser level is a good defence but needs to be kept up to date.
I must admit I don't use any of this stuff at home aside from malwarebytes and yet have never been infected by anything (Although I must admit I dodged a bullet with conficker as I was still using '98 as my primary OS back then, and it's immune

), which just goes to show - A bit of tech sense and little thought will do way more than any operating system or updates!