If you're upgrading your MOSS 2007 (Microsof Office SharePoint Server 2007) from Beta 2 TR to the final RTM release, you probably know you should be following the steps described at http://technet2.microsoft.com/Office/en-us/library/3df597d0-bad0-4c73-9c26-a10bb80449881033.mspx?mfr=true
However, if you just want to move just MOSS 2007 Beta 2 TR content, there is a simpler way. You can simply move the content database and use it in a fresh install of MOSS 2007 RTM. You basically do a backup of the SQL Server content database (make sure to get the right one) and restore it at the target server (or you can also do a database detach/attach). Then you can use that content database when creating a new web application on MOSS 2007 RTM farm.
If you're doing this on the same server, you can simply uninstall all the beta components (including the .NET Framework 3.0 RC), remove all databases except the content databases and install all RTM components.
Please note that you will need the user account used to access the database to own it or to be in the sysadmin role for that server. Having just the dbcreator plus securityadmin roles works fine if you're just creating new databases, but it will not work in case you're reusing the existing content database.
Also note that this is definitely not a supported path for any other SharePoint 2007 Beta 2 TR databases, including configuration, SSP, search or content for profiles (my sites). You can use this only if you can afford to discard my sites, user profiles and all other SSP data and farm configuration.