Mac OS 10.6 'Snow Leopard'

Instructions for creating a bootable disc for Mac OS X 10.6:

Please Note: Burning a DVD of this image requires a Dual Layer DVD capable computer.
  1. Boot your computer into OS X
  2. Go to Applications->Utilities
  3. Double-click on 'Disk Utility'
  4. Select 'Burn' from the 'Images' menu
  5. In the 'Open' dialogue which appears, select one of the images you'd like to burn to CD or DVD.
  6. You will then be prompted to insert a blank CD or DVD; do so and the burn process will begin.
For alternative installation methods that do not require burning a DVD, see How to install from a DMG.

If you are using Bootcamp, you will need this ISO image to add Windows Support,

Useful references from Apple:
Technical Specifications