Great for emulation projects- There is no DOS in Windows XP! What is called the “command prompt” is not really DOS … it can be thought of as more of a simulation of DOS. Windows XP (and Windows 2000), unlike Windows 95, 98, and ME, are NOT built on an MSDOS foundation. So, while this makes for better speed and stability, it also makes for sometimes lousy backwards compatibility. Link.
How to get DOS games to work in Windows XP