My company has an existing ASP.NET application and we have a requirement from the client that several portions of the site need to be harnessed under some sort of content management system.  DNN meets all the client's requirements for the content management system so I am investigating whether or not it's feasible to have DNN host portions of the site and maintain the content, skins, and all that while letting our application handle all the other pages.  Some of the pages that need to be served by DNN contain some dynamic functionality used by our application - the login page, for example.  On the login page we have a header, some navigation, some text and images as well as the text boxes for username and password and a login button.  We would like to be able to use DNN to serve up all the static things on the page but when the user clicks the login button, we need our server-side login code to be executed.

I am having a hard time finding information that will tell me how to accomplish something like this or even which parts of DNN I should investigate. 

Can one of you DNN experts point me in the right direction?  Do I need to use the Client Callback API or create my own user controls (ASCX) or is there some other part of DNN I should be looking at to try to accomplish this?  Are there any step by step instructions to do what I'm trying to do?

Thanks in advance for your patience with me - I'm a DNN newbie but am a seasoned developer.

Mike