How do I dual boot Vista? Vista FAQs

Windows Vista introduces a new boot loader architecture; a new firmware-independent boot configuration and storage system called Boot Configuration Data (BCD); and a new boot option editing tool, BCDEdit (BCDEdit.exe). These components are designed to load Windows more quickly and more securely.

The traditional Windows NT boot loader, Ntldr, is replaced by Windows Boot Manager (Bootmgr.exe) and a set of system-specific boot loaders. In the new configuration, Windows Boot Manager is generic and unaware of the specific requirements for each operating system, and each system-specific boot loader is optimized for the system that it loads.

The complete tutorial on How to dual boot Vista is at the Vista FAQs Website @ http://vistafaqs.com/viewfaq.aspx?faq=73.