My HDD is unreadable!! I cant think of anything!!!

[LunchBox]

I was just downloadng something and i remembered downloading it before, so i tried to access the my documents folder (i have it set to my 100 gig), and it said that it wasnt there. I then went to look in my computer, and i had the default 7 meg partition from when i got my 20 gig with my hp 2 yaers ago, and my 100 gig was a letter over. I i then went and changed the settings of my documents to drive G (my 100 gig), and it said that it was there again. I went to my computer, and tried to open it, and it asked me if i wanted to format it. I figured that the 20 or so gigs of data i had on there was already lost, so i tried to proceed, and it wouldnt let me!!!!! Next was to the drive management in the administrator tools, and it said disk 2, dynamic, unreadable!!! i then tried the only option i could, which was convert to basic disk, and that didnt do anything. I looked at the properties, and it said that it was working fine!!!!!!!!! why is this happening??!! im on xp pro, and any help would be greatly appreciated. Im freaking out. I was trying to overclock my computer earlier, and the highest setting i had it to was 12x135. when i noticed this was happening, i had already had it set back to normal because my modem wouldnt work when i was overclocking it. PLEASE HELP!!!!!!!!!!!!!!!!!! i had a lot of my files on that, and a lot of them i need!!!!

[Mr. C]

BIOS set to auto-detect.
Reboot.
Run WD Diagnostics.

Any or all of the above maybe, all just basics though as I am not XP proficient

[Kheldar]

I'd try lost&found or norton utils to get your data back

then I'd run a low level format over it - WD will have a util which does this