There are two ways to manage dual-boot: 1) 3rd party boot manager or 2) WinXP managed.
To have WinXP manage the dual-boot you must install it last. I would assume, but do not know, that Vista will also have the capability of managing dual-boot. If it does, I would think it would (like XP does) automatically set up the dual-boot. The boot.ini would be changed, and you would get the OS choice screen immediately after the splash screen. The problem, however, with the XP managed dual boot is that all dual boot information is stored in the boot sector of the initially installed OS partition. There is no boot information in the boot sector of the (last) XP installation, which took over the dual-boot management. So if something happens to your RAID HDD's, you could not boot to the IDE. You must find out if Vista can manage dual-boot, and exactly how it will accomplish the management. You must understand this before you install Vista, because if it handles it like XP, you will get the dual-boot immediately upon reboot after installation of Vista, and you will be stuck with it. It will be a nightmare to get out of.
If you use a 3rd party boot manager (and I do not know whether your FastTrax RAID Manager is capable), it is installed in its own partition, independent of Windows. You tell the boot manager which active partitions you want to be able to boot to, and the boot manager will boot to one partition while hiding the other active partition(s). In this way, you can have multiple active partitions all with the drive letter C:, for example. since only one (the one you are booted to) is unhidden at any given time. The advantages of using the 3rd party boot manager is that a) it is independent of Windows, and b) if one partition (HDD) goes down, the "bootability" of the other active partitions is not affected.
As a note aside, if you have Partition Magic, you already have a third party boot manager, BootMagic. It is not a default installation of Partition Magic. You will need to create a partition for it and install it from the PM CD. Also, there are freeware boot managers, like GRUB, for example. and, of course, an array of retail boot managers are available. You should install the 3rd party boot manager before you install Vista. In this way, the WinXP partition is hidden while you install Vista, thereby averting the Vista managed dual-boot set up.
I hope this gives you an overall view of the dual-boot process.
