Apple TV (1st generation) - Manual (Page 19)

Chapter 2 Configure. 19
To finish the network connection, follow the onscreen instructions.
Connecting to iTunes
To access the content in your iTunes library on Apple TV, you need iTunes 7.6 or later
installed on your computer. See “Computer and Software” on page 9 for a complete list
of system requirements.
Updating Your iTunes Software
You can download the latest version of iTunes at www.apple.com/itunes/download.
On a Mac, you can also use Software Update to update to the latest version of iTunes.
To use Software Update, choose Apple ( ) > Software Update.
To use iTunes 7.6 on a Mac, you need to update your system software to Mac OS X
v10.3.9, or v10.4.7 or later, and update to QuickTime 7.4 or later.
On a Windows-based computer, you can also go to iTunes Help to update to the latest
version of iTunes. Open iTunes, and then choose Help > Check for Updates.
To use iTunes 7.6 on a Windows-based computer, you need to be running Windows XP
or later.