Well you can install Linux, but install OS X is a completely different story. For one, it is against the EULA to run OS X on anything but Apple hardware, for another, you cannot simply drop a tiger disc into there and install OS X, you would have to get a hacked copy. And even if you do get it running, it will not exactly be the most stable of things
So, feel free to install linux, but if you have your heart set on running all 3 major OSes (Windows, OS X, and Linux) then get a mac.