Yes, you can.
Click start, then right-click on "My Computer" and select "Properties". It should be under "Windows edition".
Well, you will either need to buy the professional edition of windows 7, or use a torrent site to get it.
Yes, you can reinstall windows xp media edition whenever you want, by just inserting an windows xp media edition CD into your computer. I don't know if you can roll it back though.
Windows 2003 Standard Edition windows 2003 Enterprise Edition Windows 2003 Data Center Edition windows 2003 Web Edition
you cant the computer has to read it before it can start
Windows XP Media Center edition is not available for purchase except with a new computer, although you can always download torrents of it from sites such as the pirate bay.
The different versions of Windows XP are: (1) Windows XP Professional (2) Windows XP Home Edition (3) Windows XP Media Center Edition (4) Windows XP Tablet PC Edition (5) Windows XP Professional x64 Edition (fka Windows XP 64-bit Edition)
Yes, windows vista is already pre-loaded on this computer when you receive it. More specifically, Windows Vista Home Premium edition.
you need a home edition CD to reinstall the windows xp home on a laptop computer. With the CD and original code.
On a mac, if you have snow leopard or above, the App Store has Minecraft Pocket Edition (you need to pay for it). As for Windows, I'm not sure.