First off, where is the database located? Is it in the default location for SQL 2005 (program files\Microsoft SQL Server\MSSQL\Data)?

Second, if you do a properties on the...

Couple of things here. First I would make sure that you are not trying to restore to the same data directory as the SQL 2000 database files are in....

Just make sure that you also grant security permissions to the new location for your backups/database location. The security setting is for SQLServer2005MSSQLUser$MACHINENAME$ SQLINSTANCE to have modify access to...