How to turn off Voice Over on Mac OSX
Turning VoiceOver on and off is generally really easy – just hold down the command key (⌘) and tap the F5 key.
It’s possible to disable this command-F5 shortcut, so if it doesn’t work you’ll need to follow these steps:
Choose “System Preferences” from the Apple () menu.
Click on the “Accessibility” icon in System Preferences, then the “VoiceOver” item in the list on the left.
Uncheck the “Enable VoiceOver” box.