Exiting Welcome/ Registration after system install

[Aussie]

Good evening... have just done a system Erase & Install for the first time. Am preparing an eMac for sale or give away. After the installation is complete it goes directly to the Welcome and Registration process but i don't wish to set it up or choose type of internet connection etc, i want to leave that for the new owner ( should there be one). There is no way to exit the pages or any way to shut the computer down, it just assumes you want to do all that stuff, i eventually turned it off at the power button on the machine.. what should i really have done ? And what will be showing the next time i turn it on.... please.