I can't actually recall any problems from Windows updates on the 3 machines I have currently running XP. There may have been (I know there have been problems with some updates), but whatever it was was fixed in the next round.
Bit odd all these people advocating never updating - I reckon the ratio of bugs fixed to problems caused must be about 1000:1
But if you can live with the bugs and security vulnerabilities that updates were designed to (and mostly do) fix, then be my guest.
I'm no Microsoft fan, as many of you know (Linux, BSD, Mac and now Solaris are more my line) but with a minimum of care and feeding XP has become a secure and stable OS that has really given me little trouble.
Vista (aka ME2) is another matter
Mac
"Bother," said Pooh as he struggled with /etc/sendmail.cf, "it never does quite what I want. I wish Christopher Robin was here.