The Nintendo Wii cannot plays CD's the format of the system does not support the way that audio CD's are made. So, therefore they can't play CD's or DVD's for that matter.
No it doesn't. The wii uses smaller discs for games. However you can put the music you want into an sd card and play the music through the photo channel.
Unfortunately not. The system has the ability to play them, but Nintendo does not have any CD Player program on the Wii, so you will only get an error message if you try to put one in.
Games for the Wi come on CD and it can obviously read these. However it will not play other types of CDs, such as PC or music CDs. It also does not read DVDs at all.