How do you master reset a Samsung T401g?

I have a Samsung T401G thats used with Straight Talk service. I need to try to master reset it because the phone has been acting crazy. It won't stop scrolling through the menu and it stays on, like it doesn't idle when not in use. I don't know whats wrong with it. I tryed tyed typing a code i found in, but that did not work. Can anyone help?How do you master reset a Samsung T401g?aryra