The last time you invoked the shutdown dialog from the Start menu icon or from CTRL+ALT+DEL, the option that you toggled was saved at HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shutdown Setting. This REG_DWORD data type can have the following data values:
0x01 Log off. 0x02 Shut down. Ends your session and shuts down Windows 2000 so that you can safely turn off power. 0x04 Restart. Ends your session, shuts down Windows 2000, and starts Windows 2000. 0x10 Stand by. Maintains your session, keeping the computer running on low power with data still in memory (requires power management support). 0x20 Stand by (with wakeup events disabled). Maintains your session, keeping the computer running on low power with data still in memory. (requires power management support). 0x40 Hibernate. Saves your session to disk so that you can safely turn off power. Your session is restored the next time you start Windows 2000. 0x80 Disconnect. Disconnects your Terminal Server session. You can reconnect to this session when you log on again.