Partition Table Broken

I have just finished the reinstallment of a new Windows XP
installation, and used something called "PC Data Recovery"
to try and get some files back from the installation past,
although knowing that this program doesn't support bad
sectors, I ran CHKDSK and it reported that no bad sectors
were on my disk.
I ran it anyway, and then while scanning the drive, a very
weird memory allocation error message came up and seconds
later, a STOP error occured.
The blue screen showed up something with alot of hex
numbers and something about "DISK SECTOR" blah, blah.
The screen was a bit distorted and the letters were
showing somesort of characters in binary format.
Now, I cannot startup my computer, my BIOS reports no
operating system found, and FDISK cannot access it either.

I went to the aid of a respected computer technician, and
he said, while I was scanning the disk for any recoverable
files, it must've somehow broken my partition table on the
disk, erasing any access to any logical drives.

Does anyone know to fix the partition table? Or this whole
solution so I can still run my computer?