"Reserved System Space" CLOGGING drives...

I use my computer for gaming (mostly) and for work. Right now it has 5 different hard drives installed, all of them are different sizes.

When I run Diskeeper to defrag them it shows the space on the drives and what that space represents.

What TROUBLES me is how much "Reserved System Space" there is on some drives versus others. For instance:

(drive / approx space taken by RSS)
74 Gb / ~15Gb + 2 Gb page file
150 Gb / 0
250 Gb / >20 Gb
400 Gb / >45 Gb
160 Gb / <1 Gb

I can't make rhyme or reason of it. Trash can only utilizes 1% on each drive and System Restore is turned off. As I begin to run out of space on one drive or another, it is really frustrating to see about 50 Gb of free space that is denied to me.

I've been through my different programs looking for what might have set that space aside, but I can't find anything. Though I am definitely NOT a master of this XP Pro system.

Any suggestions on how I might find what is holding this space and how to get my drives back?

either that, or if this is an OEM build by dell or some other manufacturer, they will set some space aside for system recovery installs or something

i don't know about diskeeper, i think u need to do some more digging and see what's on your file system