Win8 takes several clicks to shut down. Here is how to create a single click
shutdown and restart button on the Start screen and desktop:
To create a Shutdown shortcut on the Desktop, right-click on an empty space
on the Desktop and select New => Shortcut. A menu containing a option called
Shortcut appears. Click on it to open the Create Shortcut window. Enter this
command in its box: shutdown /s /t 0 (last character is a zero). Click Next.
Give the shortcut a name, such as Shutdown and click the Finish button. It
should appear on the Desktop.
You can change its icon by right-clicking on the shortcut and clicking
Properties in the menu that comes up.
A window appears called Shutdown Properties. Open the Shortcut tab and click
its Change Icon button. You can then choose an icon from the ones shown.
Right-click the shortcut on the Desktop and click Pin to Start, which
creates a Shutdown tile on the Start screen that you can drag into a desired
position.
To create a Restart button, follow the same steps using the command:
shutdown /r /t 0
From: Essential information on using Windows 8 and upgrading to Win8 from
Windows 7, Vista and XP -
http://www.pcbuyerbeware.co.uk/Essential-information-on-upgrading-to-windows-8.htm