Since he's hosting with GoDaddy and they don't let you install into the root (without some shinanigans) it gets installed into something like www.MYDOMAIN.com/DotNetNuke, I think he wants to get it out of the *.com/DotnetNuke so it's just www.MyDomain.com.
I don't know of a good way to do this with godaddy.
A couple options I played with when I had a DNN site on godaddy was a redirect from mydomain.com to mydomain.com/dotnetnuke so they get to the correct site from mydomain.com.
A frame the wraps /dotnetnuke so the site is mydomain.com but has the actual DNN site in an IFRAME. I never liked this option because the URL remains mydomain.com and never changes.
That's all I have as options. There may be some things I'm unaware of that might work, but I don't think GoDaddy is a good DNN host. My experiences with the combination have never been good.