what cheddarhead said is true; however, since you have two drives that is not
the best way to do it. right now you have XP as your OS and it works and you
obviuosly like it since you dont want to loose it. so i would suggest the
following:
1. get any info you want to keep out of the extra drive (I will call it D: )
and migrate it over to C: which should be where XP lives. once you have
everything out of D: that you dont want to loose now you are ready to install
Vista.
before you shut down insert the Vista DVD into the DVD player!
if you have PATA drives set the jumper on drive D: to master and set the ide
cable so the end connection is attached to D:
if you have SATA drives then just follow along.
2. turn off computer and unplug drive C: (if you are not sure which drive is
which right click on the C: drive from "My Computer" select properties,
hardware tab, double click on the first drive shown, select volumes tab,
click "Populate". this will give all the info you need to identify the proper
drive)
3. once drive is unpluged; both power and IDE cable, restart computer and it
should begin to boot straight into the cd. if you get a mesaage that asks "do
you want to boot from cd"; hit any key to accept.
4. now just follow the prompts and install Vista to D: and partition the
drive as you like using the Vista tool. the only option available will be the
"CUSTOM" install option.
5. once Vista is alive and happy turn of the computer and re-install C: drive.
now C: was most likely the master if you have PATA drives so plug it back in
the same way it came out and dont forget to set the jumpers (master is C: and
slave is D
now you have two drives that are bootable and two OS's that are alive and
well. if one drive dies then the other drive can boot itself.
when you want to boot into Vista you can select the drive from either BIOS
or from BOOT Menu if you have a newer computer. (on HP and Compaq just press
esc when the HP screen comes on)
you can also rearrange so D: (Vista is Master) and C: (XP) is slave. then
just make a boot entry in Vista to boot XP and you dont have to deal with the
boot order everytime.