PROVIDED, you have no data to save, you could try this method. But be warned, it WILL destroy ALL data on your hard drive.
Fortunately, you can access here through your old machine, so presumably, you can download onto that machine as well.
First, remove the cover of the problem machine if you don't know the manufacturer of the hard drive and note it.
Now go to the manufacturers site and download their diagnostic utility for checking the hard drive. This will fit on one or maybe two floppies. Prepare the disc's and WRITE PROTECT them.
Next, download the manufacturers utility for ZERO WRITING the drive. Prepare the disc(s) as before. This is a utility that effectively sets the drive back to condition it was in when new from the manufacturer. It simply writes zero's to the whole of the drive.
Now run the diagnostic utility (boot from it), as there's no point in going further if your dive is defective. This utility should tell you.
If all is well, run the zero write disc and let it take its course. This could take quite a long time, so do it when you have plenty of time to spare or perhaps overnight. Assuming this successfully completes, you should now be able to format the drive in the normal manner, using either fdisc or the manufacturers disc (a lot quicker!).
If you need further help, please post back.