If you happen to have some old real Wii remotes and controller accessories lying around, I strongly recommend you pick up a Mayflash DolphinBar [1] from Amazon for around $20.
It's basically a Wii sensor bar combined with Wii-mote compatible Bluetooth radio specifically designed to work with Dolphin (although it will also let you use your Wii-motes as HID controllers and a mouse too).
It will save you a TON of headaches in terms of getting up and running, especially on Windows.
You need a way to rip the disks. The best way I've seen is a modded Wii. I think I remember reading there are also some DVD drives that can read the disks, too. Never done it myself.
It's basically a Wii sensor bar combined with Wii-mote compatible Bluetooth radio specifically designed to work with Dolphin (although it will also let you use your Wii-motes as HID controllers and a mouse too).
It will save you a TON of headaches in terms of getting up and running, especially on Windows.
[1] http://www.mayflash.com/products/nintendowiigc/w010.html