Lifehacker.com posted an article two days ago about how users can dual boot Windows 7 with either Windows Vista or XP.
They outlined two steps. The first is about partitioning the hard drive of the PC. The second is installing the Windows 7 operating system.
The process involves a burning tool software such as ImgBurn and a partitioning software such as GParted live CD.
Screen shots are included in the tutorial to make sure that those who want to attempt this process can easily follow the steps.