When you want to turn off your computer, you do it through Windows. In fact, you don't want to turn off your computer any other way - you always want to turn things off through the official Windows procedure.
Click the Start button to display the Start menu.
Click Turn Off Computer.
When the Turn Off Computer dialog box appears, click Turn Off.
CAUTION
Always Use Windows to Shut Down
Do not turn off your computer without shutting down Windows. You could lose data and settings that are temporarily stored in your system's memory.