The basics in my experience are as follows:
1. If you have the time and tape then always run a Full catalog backup every day, if possible set it to run just after your backups and duplications have completed
2. If your tapes are sent off site then send the catalog tape with them
3. Set the DR File to go to a server other than the Master Server as you need this for a Catalog Recovery and in the event of a disaster you dont have that server. You can specify a UNC path and login credentials on the Disaster Recovery tab
4. Always setup the DR file to also be e-mailed to you - that way not only do you have it to hand but it tells you which catalog tape was written last and gives full instrcutions on recovering the catalog
5. If your tape drives tend to be busy then do the backup to disk first - as long as it gets staged or duplicated using an SLP as you still need the tape copy.
Hope this helps