Windows in Dos




That is kind of obvious, what rajorasuresh is reffering to is when in Windows * you restart your computer in troubleshoot mode to get to the command prompt and it forces you to log in to the admin account. Once in the account you are limited on what you can do in DOS because you are using the account you want to change things on.
 

You will still need the administrator account password...
Most people forget to set a password during/after Xp installation, which is why they think they can run the prompt without user log in...

If you want such a command prompt in Windows 7 its available through the installation disc under "Repair your windows" option. Should be the same for 8 as well...