|You can't run Fdisk from a hard drive; it's run either from a suitable boot disk, or in the case of earlier windows - 9x/ME (and I think XP as well) you can get to command prompt via the setup CD.|
Something to try - as it will in effect test the system out more or less fully; not the least the hard drive.
Boot with Linux CD/DVD. Ubuntu is one of the more common variants and another is puppylinux
ubuntu.com - free ISO - which download and burn the DVD - not a CD (CD is too small capacity).
Boot up with the DVD; it will load Linux into RAM only - not the nard drive (unless you tell it to - which do NOT).
Once booted to the desktop you ought to be able to locate the hard drive; and thus inspect its contents... If you can' even see the drive... There may be "sumat amiss" with it. I'm not sold yet on the idea that power surge took out the hard drive; usually it's the power supply andor RAM/CPU that go down (in my limited experience).
The OS itself might become cotrupted; but usually one can get into its boot-menu...
The mention of Partition Magic does complicate things; as you don't say how PM arrived or if tt was being used? Al the signs thus far are that it "was" controlling the boot process - which is why you can't get anywhere with a windows installation. One has usually to disable its control of the mbr (via Fdisk /mbr routine),. Also there were known issues with some flavours of PM and XP; the two didn't get along very well - and more than a few XP systems had problems with it.
Another angle to consider - and this may be easier? Use the Ultimate Boot CD:
It allows many operations normally associated with a floppy... It has (scroll down the list) - an mbr tool - which likely will do what Fdisk /mbr does...
I haven't really used this disk other than to explore its contents; and that was age ago - likely about the time that XP arrived... But it is well recognised and safe to use utility.
If the data is corrupted, can this be fixed without replacing the HDD?
Earlier (#5) you stated that there was no data etc. on the drive that needed to be recovered/saved? Is this not so - now? If there is "stuff" on the drive you'd like to recover... then the Ubuntu boot up ought to allow it - providing the drive can be accessed OK (and the data "isn't" corrupted).