MS-DOS uses far less RAM and can be used on much lower-end computers. It can be booted in far less time than Windows XP, uses less space on a hard drive (if you even use one), and applications can be launched just by typing their name.
People have had varied experiences with Windows Vista. Some have found it to be more efficient than XP; others have found it to be slower than XP.
Windows XP.
Windows Vista is notably far more secure than Windows XP.
Pretty much yes, up until Windows XP there were versions of Windows that ran "on top" of MS-DOS, but XP (based on Windows NT) removed that requirement. MS-DOS sort of lives on as the Windows command prompt which supports most of the MS-DOS commands and allows people to run MS-DOS programs.
Extremely efficient. Most people prefer Xp. Most don't need there desktops to look preety, they need performance, and Windows XP delivers that performance. Vista dose also but has so much junk on it people prefer to use XP still, mostly with business's.
You can find out more information about Windows XP activation on the official Microsoft website. You can also find out how to activate your copy of Windows XP on the manual included with your copy of Windows XP.
Windows XP is better. Vista is a better at running games, but it is slower and more problematic than XP
Not directly. You can format the hard drive and install Windows XP cleanly. You can upgrade directly to Windows XP Professional (which is more expensive).
Do more with less
msdos is text based; it is a command line xp is graphic oriented; it has pictures and graphics
Windows XP is a general name given to sevearl operating systems released by Microsft in the early 200's. These include: Windows XP Home, Windows XP Pro, WIndows XP Stater, Windows XP Media Edition, WIndows XP Tablet, Windows XP N, Windows XP K and Windows XP KN
In windows 98 and windows me, the icons have a color depth of 16-bit, in windows xp the icons have a color depth of 32-bit and so they are higher quality. Note: Windows xp more user freindly and graphics clear.