Timeout expired error while using copy database wizard
A much more efficient path than messing with that wizard would be to:


Take a full backup of your 2000 database.
Restore it to a SQL 2005, 2008 or 2008 R2 instance, all of which support 2000 databases. You can still get the evaluation edition of 2008 R2 here, if you don't have any applicable instances in place. Note that Express won't work as it has a 4GB / 10GB data file limitation depending on version.
Change the compatibility level to something above 80 (90 or 100, depending on whether you used 2005 or 2008/2008 R2) using ALTER DATABASE.
Take a full backup of this database after it is no longer in 80 compatibility mode.
Restore this new backup to your SQL Server 2012 instance.
Change the compatibility level to 110 and update statistics.
TEST.