CMS Problem with CMS
 

I have a problem with the CMS on my website my forum is located here http://www.facilityb5d.com/forum and my main page here http://www.facilityb5d.com . When I go to the main page gives me a error when I go to the forum it gives me the CMS but its completely messed up. I would like for the CMS to load when going to the root folder and forum to load when you go to the /forum. Can someone please help me out.