Prob. with Scandisk and Norton Speed Dis

I am having a problem with my disk drive.
The following is my system config:
Soyo Dragon MB
AMD Athlon 1800+ Proc.
256MB DRAM
Western Digital 40gig 7200 HD
Windows 98SE

I get an error on running Norton Speed Disk that I have errors which can be fixed by running NDD.

When I run NDD, I get the message that lost file fragments exist. I have chosen every option, and the program circles back to the original error message every time.

I tried running scandisk, but get the message that a program (or Windows itself) saved information after a previous attempt and scandisk must restart. This circles as well.

Help?

Ken