I haven't worked with dnn very much and for those who also haven't it's basically another CMS tool. I'm working on a mega menu but I am being told that I can't do something because dnn doesn't allow it. I coded a menu idea by myself (html, css, etc.) but have been told this isn't possible or it's never been done so we're not doing it. While I don't have a website example for this kind of menu being used, I know somewhere out there this menu have been used before. My question is have you ever seen this kind of menu used and is dnn really that limiting?
(The idea is that when you hover over an item on the left the information on the right changes)
This is possible with a highly customized DDR menu template.
But a good third-party theme to look at which has a custom menu implementation for DNN is Mandeep's Porto skin. Click on the link to the demonstration site and hover over the Features menu item. This is very similar to you want.
You can get tutorials on Youtube and on Mandeep's website.