Thanks to apple, we now have this handy guide
http://docs.info.apple.com/article.html?artnum=86816
For those too lazy to click the link :
http://docs.info.apple.com/article.html?artnum=86816
For those too lazy to click the link :
Don't know how to pick up and carry your iMac G5? It's easy.
Before moving your computer, make sure all cables and cords are disconnected.
Pick up the iMac G5 by grasping both sides of the computer. Carry it to wherever you wish.