Almost messed up the OS on my desktop

I almost messed up the Vista OS on my desktop computer by doing the following in Acronis Disk Director Suite 10 (running under Vista) (P.S. My original boot drive, which is a serial ATA drive, has 2 primary partition, and my current OS is running on 2nd partition, with drive letter C: , and with first partition hidden):

• Set first partition active
  
• Set first partition as Drive C
  

I think it was probably the "set first partition as Drive C) that messed things up, because after I did the above two, installed XP on first partition and tryed to switch back to original Vista by setting second partition active, I found that the feature of setting 2nd partition as C drive was grayed out. Also, because of that, I was not able to switch back to my original Vista using the boot disc of Acronis Disk Director 9 (notice that it's not 10). Eventually I had to do the following to "revive" my old OS:

• set first partition hidden
• unhidden second partition
  
• set second partition active

Still I will continue to try find a way to dual boot my machine so that I can have both XP and Vista environment.

Also I am creating a bootable CDR of Acronis Disk Director 10, in case I need it to recover the partition manipulated by Acronis Disk Director suite 10 on desktop.