Dual G4 just purchased

To use as a backupp in the event my MacPro went down for a week I bought from a friend (original owner) a dual processor G4. He wants to clear the entire boot drive, which I suppose means format it, to clear any sings of anything and start with a fresh drive. I have Leopard brand new as well as Tiger, so I have a couple of questions:
1. Can I install Leopard on this machine or Tiger is best
2. How do I format then install a new operating system on the boot drive
3. Until an emergence arises this machine will primarily be a training machine for my son to learn FCS 2 and an internet browser really, but I do want to configure it in a way that it can be a decent editing machine (not compared to my mac pro- just decent) can it achieve that?

Personally I think that Tiger woiuld have a better time with the G4.

Put the Tiger install DVD into the Mac. Restart holding down the c key. This will cause the Mac to boot from the installer. Follow the on screen directions.

--ken