Do you see a file with the extension .saver or .qtz? If so, navigate to the /Library/Screen Savers folder on your computer and drop the file in. The screen saver should show up in the list of screen savers the next time you open System Preferences. If you don't see any such file, there should be some kind of installation application that shows up when you double-click on the CD's desktop icon. If neither of these apply, you may want to get your money back...
