Hi,
If you need to restore data that you had earlier backed up to tape., then "Catalog" the tape and run a restore job.
A tape can be catlogged from the "Media" tab. Just right click on the tape and select "Catalog".
If what you intend is to restore all the selection lists, media sets, job definitions from the earlier installation of Backup Exec 9.1, then you would need to use the BEDB.BAK from the "DATA" folder that you had saved ( did you..?) to another server before reinstalling the operating system.
Copy the older BEDB.BAK into the Backup Exec directory , rename the existing one and follow the steps as per:
How to perform a Disaster Recovery of a VERITAS Backup Exec (tm) media server, including the Backup Exec instance
http://support.veritas.com/docs/261638
NOTE : If we do not receive your reply within two business days, this post would be marked assumed answered and would be moved to answered questions pool.