DOS once enjoyed the crown of being the leading operating system in the market, but is now more-or-less obsolete in current generation of GUI Operating systems, Windows XP and Vista do support virtual DOS mode but it fails to run old DOS applications and games, if you want to use native DOS applications and games in their full glory you will either need to install the original DOS on a dedicated partition as an alternative Operating System or you can simply use free DOS emulator - DosBox to emulate an Intel x86 PC running DOD with support for graphics, sound, mouse, joystick, and modem.

DosBox lets you use DOS on almost all major operating systems like Microsoft Windows XP, Windows Vista, Mac OSX, Linux and FreeBSD with ease.