Hi Mooze,
Since it is your machine, and you have hands-on, I'll take your word on the estimate of about 60gb expected useage.
That leaves you with a mystery of about 173gb ???
Until we get more information about installed programs, backup strategies, saved documents and media, restore point allocation, and temporary/temporary internet file content existing on your machine, we are in the same "guessing game" that you find yourself in.
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To possibly generate a bit more of a picture, I'll suggest a couple of Tree View type utilities in addition to what Lee has suggested.
Hopefully Lee's suggestion has already given you some clues, but if not you could consider:
SequoiaView
and/or
WinDirStat
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I'll also take a couple of "shot-in-the-dark" type guesses….
Do any of your games have automatic "Save Game" features, or do you manually Save Game?
Do you have a ton of image or media files that you may have used, but have long forgotten about?
Do you use an automated backup strategy that may be redundantly filling up your HD?
Do you regularly clear your system of Temporary and temporary internet files?
— if not consider using
one of the following:
— Windows own native Disk Cleanup - Start - All Programs - Accessories - System tools - Disk Cleanup
— Disk cleanup can also be used to delete all but your most recent Restore Points
—
ATF-Cleaner
—
TFC.exe
— Ccleaner (Registry Cleaner feature is
not being recommended here)
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I'll also suggest that you consider the following:
Most folks commonly save stuff to a folder in their My Documents Folder which resides on C:\My Documents
You can safely Move the My Documents file repository to your E:\ Storage Drive (Recommended !)
here's how
Change the Default Location of the My Documents Folder
Many folk also have specific folders that they create for saving photos, media, documents, game related stuff, etc.
If you have any such created folders, they can be cut/pasted to E:\
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From your posting of Tree Size Free (above) you can see that the Bulk of your content is made up of installed Program Files.
Obviously a small portion of that will be your XP operating system, antivirus, antimalware, which would be best left on C:\
The rest may be photoshop type applications and gaming installations which can easily reside on your E:\
Getting those Program Files over to E:\ will mean a long and tedious process of Uninstalling, and Custom Re-install to E:\
If you tackle the job of doing any/all of the above, your XP system is likely to boot faster and run with less lag/problems.
Let us know how you progress.
Best Regards
I used the Tree Size Free program again. Since Program files was the biggest, i checked there and deleted some old folders that uninstall didint remove. That only got me another 3.5GB. Well, i opened the Program Files folder to see what was being held there. Thats where i saw it, Xfire was an extremely larg folder. I opened that folder and saw a sub folder holding videos. I take alot of videos as i play COD WaW, forgetting to delete any of the old ones that i no longer need. After removing the old files, i have found the missing 170+GB of space. Had i not come here, i would have never thought to look there. 
Thank you for all your help, and introducing me to the Tree Size Free program. Consider this case closed. 
