I've moved your post to the Tune-up folder since this is the part of OneCare that monitors the status of AU on your PC.
OneCare will only accept the setting to automatically download and install updates - either immediately or at a scheduled time. All other settings are considered to be less than ideal and causes OneCare to display an at risk status.
You can peruse the Tune-up topic folder for many threads on this and my opinion on why this is less than ideal for OneCare.
The following may help you regarding the reboot issue:
Disable reboot after Windows Update: http://www.wikihow.com/Disable-Automatic-Reboot-After-Windows-Update
http://4sysops.com/archives/disable-restart-after-windows-automatic-updates/
http://www.online-tech-tips.com/computer-tips/disable-restart-now/
-steve