So my buddy gave me his old Macbook from 2007 Santa Rosa version (Had Tiger 10.4 on it) it has an Intel Core Duo in it, and at the time he had 512 MB RAM on it, so I upgraded it to 2GB. From there I wanted to upgrade the OS to OS X 10.6.6. So I got the disc, inserted it into the Macbook and began the installation process. So I get to the language part, select English, press enter and then it says "OS X can't be installed on this computer." which is pretty common to happen I found out from trying to figure out why it wouldn't work. So I was looking at some solutions that people were giving out and tried the partition deal, and I created one new partition following the instructions, rebooted and I got the same message "OS X can't be installed on this computer." I tried to reboot but noticed the only startup disks I had were the Mac OS x 10.6.6 Dvd and the Network Startup. So I tried to do Time Machine and find some backups and there are none. So basically my problem is this: I can only startup with the Mac OS X disc, and I cannot eject it, or start up back to the old version (Tiger 10.4). Any help guys? Thanks a lot!