dual booting OS or virtual OS?

[ssagge]

! would like to set up 2 OS on a computer. The present system is
Windows XP.
The second OS requires the real DOS  so that a program written only for DOS (dbase ll) can be run. 
At present this program is being run on Windows 98 which does have the real DOS

                  Any help would be appreciated (in layman terms please)
                             ssagge

[Karnac]

Have a look here.

http://support.microsoft.com/kb/306559