Unable to select any option from shutdown fly-out menu.

[M]

I am unable to shut down my PC as for some unknown reason it is no longer
possible to select shut down or any other option from the fly-out shut down
menu accessible from the start menu.
Does any one know the fix?

 

[Guest]

Try Control Panel, Power Schemes, Customize the Start button's Shutdown
button. It's set to Sleep, so change it to Shutdown. Then try and shutdown by
selecting the button and not use the flyout list. If that doesn't work, look
up Shutdown in Help. You can also use the hardware power button to Shutdown.
There's an option for that in Power Schemes, too. If none of this works, look
at the Event Viewer to see what's causing this.

 

[Guest]

When you click the button with the triangle, next to the Power and the Lock
buttons, you can choose more options like shut down, restart, log off, etc.

As Mary said, you can set the default behavior of the Power button in the
Power Options.