Before the wife really throws the pc at me

Hi All not sure if correct forum so feel fee to move. As per one of my previous posts i have let the wife loose with a spare laptop with Win8 on it, not sure if she's hating the laptop more than me at the moment so please help before the explosion comes. 1. Need to stop the laptop switching from the start screen to the lock screen when she leaves the pc for a couple of minutes. 2. she's...