Maybe I'm misunderstanding, but it sounds like you want to turn on one of the Accessibility options on your phone.
You'll need to go into Settings (you can do this by pressing the menu button and then press settings), then scroll down and you'll find Accessibilty. Once you press Accessibility, you'll want to press the check mark box next to Accessibility to download the application. And I believe the one you want is TalkBack, but this will literally tell you everything that you're touching, so if you press the Home button, it will say Home.
IF this is not the feature you wanted, I believe it requires you double tapping the check box to undo this option. If you didn't want the accessibility features, then you will probably want to turn that off, too.