How do I turn OFF Windows Narrator?

If you want to quickly exit Narrator, press Caps Lock+Esc.

Source: Windows 8 Narrator page

Caps Lock + Esc didn't work for me, but Windows Logo + Enter did:

Exiting Narrator

There are also different ways to exit Narrator. These are the two shortcuts many people prefer:

On a keyboard, press the Windows logo key Windows logo key +Enter. On a tablet, press the Windows logo button Windows logo key and Volume Up button together.

Ctrl + Alt + Delete, click Task Manager, Scroll down to background tasks, click Screen Reader, click End Task. This is the only thing that worked on my computer so I am posting this.