Acer Aspire 5580 System always restart after...

Question

Well the problem for my laptop started when i'm using it then it hang so i decided to remove the battery but when i restarted it i only see the screen having power but no display.

So i connect a VGA monitor and restart it again. After this i saw the start-up screen but when it always end-up in diskcheck then it after the diskcheck the system will restart and back to the start again. this happens when i pick the "last known configuration" and "Start windows Normally" option.

I try accessing all kinds of safe mode(with command prompt, network) but it hangs again.

Help me please... Is there a way to fix it without reformatting or deleting any important files. I need those files because it contains my thesis...