I still have some Version 2 sites running they provide everything the client wants however I changed these over to sql some time ago. Check the following take out the www in the alias - ok I know that is the setting you had before you changed servers but give it a try - secondly it depends on the setup of the new server - dnn2 had major problems with shared hosting that required a change to the core if the shared hosting permissiow ere not set correctly by the server admin. Ask the isp to set the permissions on the new server identical to those on the old server also run the dnn2 site under asp.net 1

There is or should be no difference between browsers however I have noticed that IE7 does not always clear or update its cache - so delete all temp files via tjhe tools menu and see if you get some thing different

Next check the Server Alias in your control panel for the hosting site.it should be www.missions.unitingcare.org.au 

Lastly if you isp moved you to a new server box then tell them to put you back to the orginal one till they sort out the problem

Converting from dnn2 upwards is a long process and you will most likely lose the user records it is really best to do a cut and paste from the old site to the new one.

Seconded. Maybe it's time for a migration and not an upgrade? I've seen cheap dnn hosting here and there and some of them can even grant you access to connect directly to your DB via Enterprise Manager, should you need to do some importing of data from sources like Access. Not to mention that the upgrade path process will be specially painful for you since you will have to rewrite several bits for your DataProvider.

I'd say you take a shot and copy all your previous content and install your 3rd party modules (which theoritically, they should work fine) into a new dnn installation... regarding your registered users data, you could export this data to a excel file beforehand and then use the one of the various modules out there to load this information into the dnn's membership store.

Anyways... i wish you the best of luck. Cheers!