Ok, I figured out how to get the DNS issue to resolve.  I just need to figure out how to get the default website point to the virtual directory in IIS.  I tried to point it to the directory, but it seems that it has to be a virtual directory.  How would I get this done?  I can get it done with a child site but not the default.

What web server?  Do you own the server or is your site hosted?

Under IIS, you can create virtual directories under the primary website.  The folder for the virtual directory does not need to be located in any specific location.  However, this does not sound like what you are trying to accomplish.

It sounds like you are trying to change the folder location for the primary website to something other than \Inetpub\wwwroot\.  Which is a completely different problem.

Can you provide some more detail explaining what you are trying to accomplish?

On your web server, open the Internet Information Services Manager via Administration Tools.  Expand the tree until you find Default Web Site.  Right-click and select properties.  Then select the Home Directory tab.  Now change the "Local path" and add "dnn" to the end (for example, C:\inetpub\wwwroot\dnn\".  Or, as I understood your original question, you could change the "Local path" to C:\dnn\ just as easily.  This would not be standard practice, and would likely cause anyone else maintaining this site in the future to do some serious head scratching.  If you do change your local path to "C:\dnn", I would definitely remove the "dnn" folder from your C:\inetpub\wwwroot folder, to prevent someone trying to update the site from updating the files in the wrong folder.

You will need to verify that the other settings for the default web site (execute permissions, ASP.NET version, etc) are set correctly.

This will require editing the DNS settings on your local DNS server.  Unfortunately, this is outside my knowledge.  I always let our system administrator make these changes for me.