No, you'll have to purchase a USB microphone.
Yes it does.
The Mac mini does not have a built-in microphone. External microphones must be pre-amplified (line level), so many off-the-shelf computer microphones may not work.
To attach a microphone to a Mac Mini requires a connector such as the iMic (See links below) or a USB mic that will plug in directly.
Apple makes a range of Mac computers. Most of them include a built-in microphone.
The smallest mini microphone currently on the market is 3.5mm. One can purchase very small mini microphone at electronic stores like Best Buy and Amazon.
http://www.apple.com/mac-mini/
Most desktops come with a built in screen (all in one piece) but if you get a Mac Mini, which doesn't have a built in screen, you can use any monitor, it doesn't have to be Apple.
Yes, it does have a microphone, as well as a built in webcam.
Mac Mini was created on 2011-07-20.
Yes, mac computers that come with a built in web-cam also come with a microphone and audio recording system. If that doesn't work, it is possible to attach an auxiliary microphone to a mac computer.
You cannot put a Mini Disc physically into a Mac. You can connect a Mini Disc player to the Mac and listen to it through some audio software.
No. The graphics "card" in a Mac mini is integrated into the motherboard. There are also no available expansion slots in a Mac mini. You can see some photos of the inside of a Mac mini in the "Related Links" link below.