Just bought used Imac 2.0GHz 250Gb aluminum onto which a nice seller setup/installed Leopard/Bootcamp/Windows Vista. Now I'm ready to back up the Imac to an external HD. Seller included a free Simpletech 500Gb USB external HD. How do I backup both Leopard and Windows? Do I need 2 external drives? Or partition the single external HD and put both systems on it? Use Time machine or Carbon Copy Cloner and/or Winclone? To complicate matters, the seller did not include the original Windows Vista CDs, so if I need to restore the Imac's HD after a crash, is a Windows clone on an external HD the way to go? Thanks for any help. Even the Apple store near me couldn't answer these questions which I was sure they had run into before.