On a computer with Advanced Power Management there is a Standby option under the Shut Down menu. If you for some reason want to prevent users from having this option it can be removed with the following Registry hack.
Start the Registry Editor (go to Start, Run and type Regedt32). Find the keyHKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\ACPI\Parameters. Click in the right pane and create a new REG_DWORD value. Give it the nameAttributes. Set the value to00000070. After reboot, Standby is unavailable.