Backup schecduling

[Miquel Mart?n L?pez <miquel@casal.upc.es>]

Hi all,
I am trying to decide on backup schecduling and have several things in
mind. My system is on a main hard disk, and backups are made by copying this
HD to another (equal sized) one. 

Now, the point is I have one main HD and 2 backup HD, and have two criteria:

a) Backup every one or two days, alternating the backup disks, so that the
oldest backup is max 4 days old, and the newest is just 2 

b) Backup every one or two days with the same backup disk, and make weekly
backups with the other one.

As you see, it's a compromise between having updated backups and having the
time to realize problems or intrusions.

So, just wondering, what do you do/suggest?
Thanks!
Miquel Martín