http://msdn2.microsoft.com/en-us/library/ms143393.aspx has the full list of SQL 2005 Version and Edition Upgrade Scenarios.  Just like in SQL 2000, it's basically an in-place re-install.

lol... it's throwing 401.1 (not authenticated user) errors now

Thanks for the alternate link

Security : Logins : Add New Login

Then assign the login permissions to a database either via it's properties or by going to the database and setting it there. That's...

Set up the rights so that the Help Desk people can only change login passwords for the legacy applications.

Have them use your choice of query analyzer and learn the ALTER...

AquaFold DataStudio.

Of course, I work for an educational institution, so the license is free.