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.

[1] http://www.mayflash.com/products/nintendowiigc/w010.html

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.

Oh, here we go: https://wiki.dolphin-emu.org/index.php?title=Ripping_Games#R...

Rip the ISO from the discs, then load them up in Dolphin on your Mac.