its comes up when your comp is starting up, you have to press either f1 or f2 on the boot screen, clean the c drive dont delete it, all the system op files are in there, i think most c drives are ntfs a d drive is fat32, mine is anyway, if whats the total size of your c drive?
my d is used for 1 thing and 1 thing only........ thats where i keep my porn
i've attached 140 ways to improve xp to the post, that might help
use system mechanic pro to clean it, the trial demo is fully functional so that should sort it
system mechanic prob best to leave it running overnight on totalca