Restore Macbook

Hello, I am upgrading to a nre 13' macbook pro and leaving my 4yr old macbook to my dad. I've found instruction on the apple support website on how to use the Migration Assistant so I can transfer all my files from the old computer to the new one.

I would like to know, ocne I've transferred everything into the new one, how to delete all the information from the old one. Is there a way to restore the computer to the original settings or something like that ?

Thanks !

You can use the disks that came with the old one to wipe and reinstall the OS! Here're some links that may help you with that:

Lion
Older (10.6-ish)