Due to some issues with the SP2 disabling applications ( read here
http://tinyurl.com/68nyz), I recommend that you turn off automatic update in XP.
Go to start / control panel
select Automatic update icon
uncheck automatic update (recommended)
check notify me but do no not download.
There are problems with antivirus programs/quicken and probably conflicts with your own firewall.
I also suspect that some casino sites may become inaccessible.
Give it sometime before you download the upgrade until IT managers at work and other entites figure out the extent of the problems.
JAque