In case you would like to install Debian on a system running Microsoft Windows, you could use win32-loader (aka "Debian-Installer Loader") from the Debian mirrors (win32-loader.exe). BUT a number of virus scanners falsely claim it may contain a virus, see /SuspectedVirus.
- No installation CD is required to be obtained, burned/mastered and then booted.
- Your existing Windows system can be preserved.
win32-loader (Debian) article on Wikipedia