Recovering a Partition on Win98

Over the last few weeks i have dug a very deep hole, and just as i was getting out of this hole, i hit a wall.
It all started when my mobo broke due a short circuit caused by a faulty USB port that was causing problems. I bought a new ASUS mobo, and then had to buy a new case to accomodate it (i had a package computer previously). I set all of this up, and then whilst running my system, my Windows XP refused to accept the new mobo, as the OS was assigned specifically to my old motherboard. This didnt prove to be too much of a problem, as i had a copy of Windows 98 that was no longer in use that i could use instead.
Installation went fine, if not monotonous, but i then found that my 80GB Samsung Hard Drive had only 4GB space on it - the space that was originally used by the recovery partition. After some research, i came to the conclusion that this was due to tthe fault with windows 98 with recognising Hard drives over 64GB.
This proved to not be the problem.
It transpires that the 75GB partition that made up the useful part of the drive was made in a partition by Windows XP, and apparently it cannot be read by 98. After running fdisk to try and remove the partition, i found that fdisk cannot do so due because the drive is 'unable to be locked'.
Could someone please advise me on a solution to recovering this large amount of Hard drive space that i do need. All help and advise is much appreciated.

Thanks

P.S If the solution could involve spending as little money as possible that would be great, as i have no money and all savings i had went on the new parts.

 

Drazzard, but do you have a backup as all data would be lost