If you haven't already read this tutorial http://www.dolphin-emulator.com/connect-wiimote.html.
Regarding the garbled noises your Wiimotes speaker may be bad, simply mute the volume by pushing the Home button and turning down the volume and while your at it I'd recommend turning off Rumble as it drains the battery faster. Also if you do want to hear the sounds make sure Enable Speaker Data is checked in the Wiimote settings on Dolphin.
Layin down enjoying the fun unleashing the power of the sun and capturing them all until I'm done.