Missing Disk Space: XP on Inspiron Mini 910

I recently purchased an Inspiron Mini 910. I bought the Ubuntu 8.10 Model which had the intel Atom 1.6GHz Processor, 1GB of RAM, 4GB SSD Drive, and etc. Now, I just recently purchased a Samsung External USB DVD Drive, and used it to install a copy of Windows XP Professional. Once everything was installed, drivers and necessary programs, disk usage was at 2.3GBs (with hidden files toggled on). My Hard drive reads as 3.5GBs, which is to be expected. However, my hard drive reads that it has only 28mbs left. I thought it might be the paging film, but it couldn't have been. I disabled that right after the install and allocated it to a 2GB Sandisk SD card. I checked all temporary folders and emptiesd those, and I deleted and disabled the restore point feature. I ran the disk cleaner and still I have this problem. Any ideas as to what else could be taking up this mystery disk space? And if anyone can offer any suggestions as well that would be awesome.

Also if it is any help I have installed programs like MSO Word 2003, PowerPoint 2003, Corel Painter Essentials 3 (for my wacom tablet), and Photoshop 7.0. I want to note I thought that temporary files could have been used in Corel or Photoshop, since those are intensive, however I checked any of their temporary folders and cleaned them, but the files were small regardless.

Oh and another note, when I do go into the paging file configuration tool, it says I have 1300 mbs available. So I am unsure if I configured the paging file correctly. I right clicked My Computer, whet to Properties > Advanced > Performance > Settings > Advance > Virtual memory > and then I configured it so that my C drive had "No Paging File Selected" And so that my G drive (a 2GB SD card) had 1500mb aloocated for virtual memory.