Space reporting error and cd key recovery

I'm running windows xp pro and i think it's reporting the wrong amount of free disk space on my system parition. When i check the folders individually it tells me that i'm using 7gb, but when i check the drive as a whole it says 15gb are being used. I tried running the xp scandisk, but when it gets to phase 2, it stops and says the disk could not be checked. any ideas what i can do to fix this short of reinstalling.

Also, i have two copies of xp and i can't remember which copy was installed on which puter. is there any way to find out what cd key i used on what computer?

When you checked the size of the folders on your disk, did you make sure to check hidden files and folders and your page file, too?

As for Scandisk dying on you, try typing CHKDSK /F at a command prompt. Windows will most likely tell you that it'll run CHKDSK at the next boot, so reboot your system and Windows will check your hard disk for errors and correct them.

tried that, to no avail, so i ended up reinstalling.

I split the partition into two smaller partitions, one system and one junk. Unfortunately windows decided that putting the junk partition after the cd rom drive was a good idea. I remember in 98, you could tell windows where to start lettering the cd rom drive from and thereby stop it from having any drives, be they network or local, from being after the cdrom. unfortunately i can't seem to find this option in xp pro. anyone know where it is?

Right-click My Computer and select Manage, select Disk Management. Right-click on a partition or disk and choose "Change Drive Letter and Paths...", that'll let you change the drive letter.