Zone Alarm has a new version to correct the recent related problem , so if you can
uninstall the old Version, then install the New ZoneAlarm you won't need to worry
about uninstalling the Missing Windows Update that started the mess you got. I think
I would just try that.
You can try System Restore to before SP3, but with
all the Problems you could also wind up worse off.
I would suggest backing
up all your important data at this point. Just in case.