Fine, I will conceede my point. Alot of CS courses require you to use Linux, and many people still prefer it for some reason.
Yea, as previously stated, avoid PPC Fedora. Just go to Ubuntu's site and download the ISOs for mac. Also, Ubuntu has a great program where they will send you free CDs of the OS (they pay for shipping and CDs).
Anywho, Ubuntu is essentially a simpler to install version of Debian with some extra bells and whistles. Go Ubuntu!