Hard Disk error...

This may NOT be an actual hard drive failure, it's possible (based on the red 'x' in the left of the error box) it's actually malware masquerading as a real system message.

Before we assume it's a legitimate hard disk error, click the little up-arrow immediately left of the daemon tools icon on the bottom right of your screen, if you see a red 'X' there too, right click it.

If it pops up another window with various other errors on your system, this is NOT windows - it is in-fact malware that has gotten on your system.

In any case, it won't hurt to scan your PC for malware before we assume it's a genuine failure.

I've not encountered this particular thing myself but the URL I've got information from is here:

http://answers.microsoft.com/en-us/windows/forum/windows_7-system/windows-detected-a-hard-disk-problem/04a301bc-e063-429d-ac93-f8f4062e5d62

Scroll down until you see a post by FHC Tech - dated 20th December 2011.
This is the post you need to look at and follow the instructions if possible.

In short - you need to download (on another PC if possible) malwarebytes antimalware (free) edition, there is no portable version of this software but it won't harm your PC if you install it.

Whatever you do - DO NOT RUN the software in normal mode, at the end of the install it should give 2 options, update malwarebytes and run malwarebytes. Ensure only the 'update' is checked, this will ensure you have the most up-to-date definitions.

Reboot your PC into safe mode, open malwarebytes and run a FULL scan of all drives and let it do it's job.

Now it is possible that the malware would stop malwarebytes from running, in which case - you need to download this: http://www.malwarebytes.org/products/chameleon/ to a USB stick, make a new folder on your C: drive and copy the download to the folder.

Get back into safe mode and then you then need to run each file 1 at a time until it remains on the screen, then follow the on-screen instructions as this should allow some kind of scan to take place.

Failing that - you can always try the ESET Online Scanner, however this may have limited success, but I'd certainly start looking at it as if it was malware, rather than a hard drive failure first of all.

If you are convinced it's a real failure, then I'd back up the contents of those drives if you can (do NOT click the 'back up now' link on that window, use Windows Backup or something else instead) - then open the command prompt and type the following:

chkdsk <drive> /F /V

(Replace <drive> with the letter of the hard disk, e.g. C: or D:)

This will scan the drive and fix any file-system errors it finds, it will NOT scan the surface (at the moment).
It may say it can't do a chkdsk because the drive is locked or you need to unmount it, press 'N' and then answer 'Y' for allowing it to do it at next boot.

Hope this helps.