1) NetBackup catalogs and part of the catalogs are clearly explained in NetBackup Admin Guide I.
You have not selected your NBU version and I seriously doubt that you are running NBU on Windows XP.
You can find links to all NBU manuals in 'Handy NBU Links' in my signature.
NBU 7.1 Documentation: http://www.symantec.com/docs/TECH154178
NBU 7.5 Documentation: http://www.symantec.com/docs/DOC5138
NBU 7.6 Documentation: http://www.symantec.com/docs/DOC6488
Topics to look for in the Admin Guide:
About NetBackup catalogs
Parts of the NetBackup catalog
2) Retention level/period of Catalog Backup is selected by the person who configured the Catalog backup.
Have a look at the schedule(s) in the Hot Catalog backup policy.
