Yes
no unless your willing to void your warrenty and a risk of bricking/damaging your wii. if so save homebrew onto an sd card and copy and paste to wii memory. then i think you can play them.
It's very, very unlikely. If you have a DVD/CD combo player, then perhaps, but you cannot if it's only a standard CD player.
yes it does
Yes. DVD players can play music CDs. Blu-Ray players can also play DVDs and music CDs as well