Hard Disk Failure?

I trying to format one of my partition. When i reaches 83% it hangs (slows
in fact).

I tried to:
format by right click in My Computer.
format by changing from NTFS to FAT32.
run some other third party programs in DOS mode. Which shows some ectivity
but didnt pass 83% after long time and shows "Bad" there.
Run Scandisk which says "No Problem".
format using XP CD. same result.
Some programs, run in dos mode, shows errors at that point i.e. 83% (counted
90 till i stopped test).
Powermax says disk is dying.
quick format works fine.

How can i stop further damage or spreading bad sectors to my disk?
And full format my disk properly?