I ran a Dell scan early this morning and got two failures pertaining to the Hard Drive, the Targeted Read Test (WHD20-XKN) and SMART Short Self Test (WHD16-8QA).  Exactly what do these failures mean and what are the implications? 

My desktop still runs pretty good, but when I try to do a Drive Medic; Repair Hard Drive Problems with my iolo System Mechanic in an effort to fix the Hard Drive, the application always freezes when it reaches Stage 2 of 5 while the Drive Medic is verifying indexes.  Does this mean my computer's Hard Drive has serious issues and how do I fix it? 

Any and all suggestions & help is appreciated!