Are you refering to the database for VirtualCenter? If you want to keep things simple, set the database recovery model to simple and then you only have to worry about running full database backups. The backup could be scheduled to run nightly and you could keep 2 or 3 days worth of backups on disk before deleting them. The backups you take to disk should then be backed up to tape as well.
If you have to recovery a databse to a more recent time frame and couldn't afford to go back to the previous full backup, then you would want to set the recovery model to full. you would then need to schedule a full backup (could be nightly or at the end of the business day) and then also schedule transaction logs backup jobs to run more frequently. The frequency of the transactions log backup jobs would depend on the importance of the database. For a more critical database, you might want to run the transaction log backups every 15 minutes. In the case of a database failure, you could recover the database and loose only 15 minutes worth of work. Again and depending on your needs, 2 or 3 days worth of backups on disk should suffice and you should also backup the full and transaction log backup files to tape.
