To see which Operating System you have take a look at the bottom left of your computer screen. If you see a button that looks like this: then you have Windows XP. The tutorials for your Operating System are here: Windows XP Tutorials. If, however, you see a round button like this one: then you have either Windows Vista or Windows 7. To check which you have (Vista or Windows 7) click the round button once with your left mouse button. You'll see a menu appear: From the menu, click on Control Panel on the right-hand side. You'll then see a new screen appear.