My first guess would be you would need a third party OS Bootloader Program to sort this all out.
Acronis has that as part of the Disk Director Suite, and there is a freeware one that "sounds like "GAG" (or something). (Not an inpriring name for something this important... <grin>) Rick Glazier From: "Tony Riederer"
I am wondering if there is any problems or special things that need to be done here. I have Vista Ultimate 64 on one of my puters. I have Windows 7 Pro from my school that I would like to install on the same machine and dual boot them. It is not an upgrade edition. Just wondering if anyone knows if there is a certain way to do this.