If this problem has begun fairly recently, try doing a System Restore to a day/point before the problem. As it won't load properly, use the 'Safe Mode with a Command Prompt' option - see click here for instructions.
If the above doesn't work, it could be hardware related & we'll have to try something else. Is the laptop under warranty?
Btw, what do you mean by 'flatten'? Does it involve some kind of road roller? G