By chance I happened to meet this real computer expert yesterday, he builds computers etc and is a lecturer on them at University.
He told me that XP will not allow the use of DOS, and that it (XP) is very particular which programmes IT allows you to run.
The only way around it he said, was to completely wipe my new hard drive, then electronically divide it in two, and instal XP on one half and 98 on the other half, which I am definitely not going to do.