[roi]

My friend got a new computer, preinstalled with vista, and now she have to change it to xp and needs my help. I've never done this before until now. I burned the image, booted the cd and now have to partition my drives. I assume this is like some kind of formatting. My question is am i just supposed to partition/format my main drive C or am i supposed to partition/format both my main drive and the recovery drive D. Will partitioning/formatting the recovery drive get rid of critical system processes? What am i supposed to do? Partition/format drive D or not?

Thank you for the help