When you open up Disk Manger (right click my computer > manage) and next to your 1TB drive (that incidentally houses all of your FRAPS clips and finished projects) there is a “AT RISK” icon and text.  Heed it! Else you will find yourself running chkdsk to try and recover whats left.  Which will fail due to the fact that the HD now sounds like it has small metalic rocks or equivilant inside and chkdsk has failed on you with an “unspecified error”. Heed the warning and get those files outta there!