mouse is used to select various options on the screen. it is also used to open & close files.
green
I would recommends the Wireless Mighty Mouse by Mac.
a PC controller is a mouse
If you MAC is old then it uses a different motherboard than a PC. These days MAC also uses intel processors so in theory you can use the same motherboard as PC but there may be problems in adding the peripherals like MAC's keyboard and mouse to the PC motherboard and vice-versa. It all depends upon what you have got.
2 and they are keyboard and mouse
Throw it away.
PC mice commonly have physical scroll wheels and right click buttons. The new Magic Mouse for Mac has them, but they are touch sensitive, as is the entire mouse's surface.
worse
No, not on Minecraft PC. You just use your mouse and keyboard.
Everyone, Who uses a PC without network connections.
The Crystal Monkey PC Laptop Mouse Wrist Cushion was not designed to be heated, and is not recommended.
Generally it depends on the type of mouse and brand that one is buying. A PC mouse will cost someone around 15 to 25 dollars, or about 40 dollars for a high end one.