Hey people, I was using my computer normally one day when all of a sudden it started acting funnily, freezing up and what not, Opera browser became unresponsive and then eventually everything else beccame unresponsive so I was forced to hard reboot the laptop by holding the power button down.
So I turned it back on, (I have windows 7), but instead of the windows 7 boot thingy showing up (the glowing windows icon) I got the "windows is loading files" like on the install disc. Then the screen went black and nothing happened. So I got my W7 install disc out, bD with it to NTFS.
Then I was able to reinstall windows 7 from the disc, at this point I just thought there was a virus that screwed my OS up and reinstalling would fix it. So I installed windows again and it worked fine for a short while (1-2 days) but then the same thing happened, things started not responding and explorer.exe starting crashing alot, then eventually it BSOD'd and wouldn't work again. I've since reinstalled my OS about 6 times but the same thing continues to happen after no more than 2 days it will lock up and completely stop working and I can't even boot it.
You could also use either of the above diagnostic utilities to perform a complete surface scan. HDDScan will identify "slow" sectors, ie those that require one or more retries before they can be read successfully.