Running ME but as crisc pointed out why doesn't the MKB article help out...?
Standby Missing From Windows Shutdown Dialog Box
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VXD\VPOWERD
Verify that there is a "Flags" value and a "SuspendFlag" value. If these values do not exist, quit Registry Editor, and contact your hardware manufacturer for further assistance. If these values exist, verify that the data value of the "Flags" value is greater than or equal to 200. If it is, modify the data value of the "Flags" value by subtracting 200 from the current value. For example, if the value is currently 310, change it to 110. Change the data value of the "SuspendFlag" value to 0 if it is not already 0.
FOR WHAT IT IS WORTH...my registry key values are as below, Standby is INCLUDED option on Shutdown
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REGEDIT4
[HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\VPOWERD]
"SuspendFlag"=dword:00000000
"StaticVxD"="*VPOWERD"
"Start"=hex:00
"Flags"=dword:00000000
"SuspendHasWorkedFlag"=dword:00000001
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REGEDIT4
[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer]
"Shutdown Setting"=dword:00000004
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Also topic available at:
Windows Remembers the Previous Shutdown Option
smitee