With the Digital AV Adapter (sold separately from Apple), setup is instant. Everyone sees what is on your display on the big screen.
Plug in the Digital AV Adapter (also sold separately at Apple stores or website), and it works, just like that. There are no settings to tinker with or configurations to figure out.
The adapter also works with audio. One end plugs into the 30-pin connector on iPad, the other end plugs into your HDMI cable. The cable plugs into your HDTV, projector, or other HDMI-friendly screen. There is also a second 30-pin connector to USB cable to charge your iPad, so you don't have to worry about running out of power in the middle of a presentation or movie.
Some older Apple products may require you to download a special application and follow specific instructions.