If you like your PC to boot just as fast as possible then the new Windows 8 lock screen may not appeal. Don't worry, though, if you'd like to ditch this then it only takes a moment.
Launch GPEdit.msc (the Local Group Policy Editor) and browse to Computer Configuration > Administrative Templates > Control Panel > Personalisation.Double-click "Do not display the lock screen", select Enabled and click OK.
Restart and the lock screen will have gone.