Database Restore Failed Due to Incompatible Version of SQL Server
+1 to Doug L., I'd recommend the same (export all data and structure into SQL script and data dumps, then import) but on top of that: if you can connect the two DBs you can cross-server SELECT/INSERT INTO the tables and data from old DB to the new one; you can also try upgrading the RTM server (if you are allowed to do that) - I'm unsure on this but I think if you install SP on the RTM it'll be considered as same version as the other guy.