Running a DOS program in Windows XP

I have just updated to a new Windows XP laptop from an old Windows XP laptop and have copied over an old DOS program called GEM (an old but very good design package).

I can run GEM in Windows XP, however, when I try to open up any of the copied drawings I get the following message:

"The NTVDM CPU has encountered an illegal instruction." This sentence was followed by obscure numbering etc..

Now it just bombs out and closes the application.

Are there some settings I could tweak to make it all work? Thanks anyone