I've been getting a lot of comments on my post "SP2 breaks Windows Firewall/Internet Connection Sharing Service" asking for help.

In general I've found that by removing SP2 via Add/Remove Programs in Control Panel and then re-installing it most issues can be resolved. BE SURE TO BACK UP ANY IMPORTANT DOCUMENTS TO CD, FTP, WHATEVER BEFORE REMOVING SP2...I HAVE SEEN THIS MAKE IT NECCESARY TO RE-INSTALL THE OS ON A FEW OCCASIONS!