Can't upgrade what? OS, Ram, HD?
The mini is the lower end "Desktop" model so there really isn't much you can upgrade anyway.
Apple has a list of the latest Operating System that your version Mini will support meaning it should work without any tweaking. (By the way Apple no longer is actively supporting any of the PowerPC models) People have used higher OS versions without much problems, but again if any problems pop up Apple won't help. If your looking at upgrading the ram and Hard Drive then again look online and online stores do still sell some of the older Ram and Hard drives.
This will depend on the specs of the Mac mini in question but in general, yes.
A total of 16gb of memory can be gained using a memory upgrade on a mini mac as the mac has only 2 internal memory slots. These slots should be fitted with 2 identical memory chips in size and speed to allow for best performance and to stop the unit from freezing
No, you have a Mac Mini using the Power PC G4 processor. Only a Mac running the Intel Processor can run 10.6.8 Snow Leopard. You can however install 10.5.8 Leopard on your Mac Mini.
http://www.apple.com/mac-mini/
Mac Mini was created on 2011-07-20.
10.6.x is no longer actively supported by Apple on anycomputer now so they will not be able to help you even if your mini is supported. If you have any problems the Apple forums are there to help.
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.
A Mac Mini is a computer. It can be used with any screen and keyboard.
After Mac OS X 10.4.11 (Tiger) you need to buy an upgrade to Mac OS X 10.5 (Leopard) the current highest version of which is 10.5.8. Leopard will be as high as a G5 can go as 10.6 (Snow leopard) requires a newer Mac with an Intel processor.
To legally upgrade from Mac OS X 10.3 to !0.4 you will have to purchase a copy of 10.4 (Tiger).
Mac