Windows Vista Service Details
Allows you to download/install updates and patches from Microsoft.
Enables the detection, download, and installation of updates for Windows and other programs. If this service is disabled, users of this computer will not be able to use Windows Update or its automatic updating feature, and programs will not be able to use the Windows Update Agent (WUA) API.
Consequences of Stopping:
Windows Update will not function. Not just the automatic service, but running it period.
All services listed in 'Required For' will be unable to function