Hi Tony Draper,
The NTFS partition will not be very FDISKABLE. I have always used another program called DELPART which works perfectly with NTFS and FAT16/32 partitions, to delete a partition.
Here is the link to DELPART (I did a Google search):
http://www.juliatexas.com/delpart/delpart.exe
Now, this is a known and tested partitioning tool so don't worry, it is not buggy and will not mess up your system.
You can also use the native WIN2000 installation CD to start a Win2k install and format/delete partition from there.
Hope this helps.
John