With this kind of error the line numbers are often misleading.
My first guess is that you have a typo somewhere in user.config like an extra angle bracket or a missing one or the typo could be in Web.config.
My second guess is that another web.config file is interfering, possibly there is a web.config file in the folder above where you have mojoPortal installed.
I would have thought that the wwwroot folder at your host would be the root of the site. When you ran the setup page was it running from http://yourdomain/Setup/Default.aspx or from http://yourdomain/somefolder/Setup/Default.aspx?
Hope that helps,