So, I have been digging around in the database I have and the database that was created as part of the install, as well as doing more digging across the forums trying to understand the issues here as well as trying to work out if this is going to take much longer to solve.

A couple of tables are mentioned in a few of the posts I have read

PortalAlias, PortalLocalixation,PortalSettings.

These have major differences between what has been created via the install and what I am trying to connect to in my existing database, I guess my question here, is do I need to make changes in these tables in line with the created database, or should these just work?

OK, so I have this finally working, I had to do a lot of digging. but finally fixed why it's wasn't showing correctly.

The site created on the platform install was fine, the issue was when i changed this to be my old database, and old website.

In the database is a table called PortalAlias. This had the name of the current hostname from the old server, which is going to be changed when it is migrated.  I was creating the new host with that name, but DNN was looking for the old one, so not opening up the site correctly.

I guess if you are just recreating the site from one to another this wouldn't be an issue.

I have managed to upgrade from 7.2.2 to 7.4.1, however this is giving me some issues with screen redirects, which i need to deal with, and just for testing purposes i added an upgrade to 8 this has given me errors to do with solpart, which again I will need to work through when i do that correctly, but for now I have at least one upgrade done, with at least no errors, or issues at least opening the site afterwards. 

Thank you for all the help with this, I know it was a struggle, at least for me, but I got it done in the end.