I know this isn't recommended but my development server is 2008 while my production server is 2000.
What is the easiest way to copy databases back and forth? For example, I just created a database with a robust date table which I intend to use in my queries. I figured the easiest way would be to back up the database and restore it to the other server.
What is the most expedient way to do this in either direction?
Backup-copy-restore is just as fast if not faster than detach-copy-attach. Especially if you get great compression with the backup--that copy step will take a lot less time!
You can use BACKUP DATABASE and RESTORE DATABASE, or sp_detach_db and sp_attach_db stored procedures.
Read this article about transfer SQL Server databases to a new location: "Moving SQL Server 7.0 Databases to a New Location"
Have you considered the Microsoft SQL Server Database Publishing Wizard? It will script your database, including the data to TSQL.