I don’t know if it’s hidden, but one way to find out is to go into Control Panel -> Folder Options -> View and scroll down until you find the selection that hides folders. If that box is checked, uncheck it then see what you get when you click on C:\users.
Hang on, I just had a thought. You’re only getting the window you posted after clicking on User? When you log onto your computer are you going in as administrator or regular user? Have you set up an administrator/regular user account in Win 7? If you haven’t set up an account in Win 7 that may be the reason you don’t see anything but the window you posted. Win 7 doesn’t know you want to get into a specific account. I don’t know Win 7 that well to tell you how to set up a user account, so if you do need to set up an account Google will be your best friend to find the information.