Copy database from SQL Server 2000 to SQL Server 2005

I was trying to transfer a SQL Server 2000 database to SQL Server 2005 using SQL Server Objects Task. However, The following error message was encountered:

"[Transfer SQL Server Objects Task] Error: Execution failed with the following error: "Cannot apply value null to property Login: Value cannot be null..".“

can anyone suggest me what is the error here?

Is there any other way possible to achieve this(transfer of database). The objects to be transferred are tables, views, stored procedures, user data types, and user-defined functions. The logins need not to be transferred.