|That's a Windows problem you have there, then, most likely. It doesn't sound like a hardware problem at all.|
Somehow, your drivers have been corrupted, or some software is trying to load which is causing Windows to have a 'seizure'. You could spend ages trying to track it down, or you could format the hard drive and install Windows again. you'd lose all your data if you did that.
Try booting Windows in 'Safe Mode' (by pressing the <F8> key while Windows is first loading) and see if it runs that way. If so, it may be recoverable.
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