>> ... so I go into Start -> cmd ->...??...
I don't have access to a Windows XP system, so I'm not sure, but probably something like:
Open the Command Prompt window by clicking the Start button, clicking All Programs, clicking Accessories, and then clicking Command Prompt.
Once the window is opened, get help by typing in help
It maybe won't give you access to files on your separate DOS partition (depending on how this is set up?), but it does give you access to a pseudo-DOS environment, under which there are plenty of DOS utilities; you can probably run many old DOS programs in this environment too.