By default Windows 8 boots in to a lock screen, which is quite useful for mobile devices to stop entering commands accidentally. When it comes to your desktop it might be extra step that will waste couple of clicks. Simple Windows 8 Group Policy hack will allow you to disable the lock screen.
1. Open Run Windows
Press Windows Key + R (For more Windows 8 keyboard Shortcuts)
2. Start Group Policy Editor
Type gpedit.msc on Run Windows and click OK
3. Go to Personalization folder in the Local Group Policy Editor
Left menu on the Group Policy Editor follow the folder path
User Configuration> Administrative Templates> Control Panel> Personalization
4. Open the Do not display the lock Screen Setting
Double click the Do not display the lock screen setting in the right hand pane if the Group Policy Editor.
5. Enable Do not display the lock screen.
Select Enable and click OK.
6. Restart the Desktop and lock screen will not trouble you any more.
Click the link for useful Windows 8 Tutorials