2 questions please

1how can i change a databse file name easily in sql 2000 and 20005
2 i tried to attrahc a databse and this error message appears: in sqlserver 2000 and 2005
Could not find row in sysindexes for database in ID 6, object ID 1, index ID 1,Run DBCC checktable on sysindexes
Could not open the new database

how can i attach the database what did i do bad?
thank you

Luis Martin