Windows 7 not booting properly

[L1ght]

Hi guys, when I turned my computer on today, windows 7 decided not to boot properly. It gets to the screen where you type in your login but the screen is totally black and all I can see is the cursor. Has anyone got any ideas? I'm currently running in safe mode. Cheers

 

[L1ght]

Its kind of working now ok, I installed AVG and it started working for some reason? No viruses were found so this is kind of wierd. Still on booting up there is more of a lapse with a blank screen.