so a friend of mine recently just purchased a new 2.4 ghz macbook pro. It comes with Leopard and everything pre-installed and it also comes with a MAC OS X Installation CD.. I have the old macbook pro with tiger on it, is it possible for me to install Leopard with the CD he got inside the box ? Will all my information/files/software get deleted or is there an option as you install it to keep all your information and just install Leopard ? Thanks in advance guys, very much appreciated.