The other day my friend was going to shut down his laptop after a meeting and Windows in the course of the meeting, had downloaded a substantial amount of updates that were set to install if he shutdown the laptop. Not wanting to sit there, he hibernated. I could not give him off the top of my head the way to shutdown without installing but later I know that I have dealt with this multiple times.
There was a hack out there to do this, but I have set this for thousands of machines through Group Policy.
Start GPEDIT for local machine or GPMC for domain level. In User Configuration, Administrative Templates, Windows Components select Windows Update. Double-click Do not display “Install Updates and Shut Down” option in Shut Down Windows dialog box in the Settings section of the Group Policy editor.
Select Enable and then click OK to save the changes.