In setting up a dual boot system, is there any advantage or disadvantage to setting it up on one disk with partitions vs. using separate disks for each OS. My thinking is that any operating system technically sees partitions as separate disks, so partitions on one disk should look and feel like separate disks. Wrong? I am planning to set up one dual system with Vista and XP, and another system with two XP installs. From what I have read here, setting up Vista-XP dual boot is not a slam dunk operation with OSS, so I am looking for the simplest approach, even if that means not using OSS.