If you ran the standard XP Disk Cleanup I think the figure you quote is what allowing D.C. to compress files will free up on your hdd not the disk space used by compressed files..
Check the number of days option in Disk Cleanup for compressing files, you wouldn't want to delete a compressed file just a couple of days old??
I disagree with Merlin. The info2 file in the recycler to which he refers contains the complete paths/filenames of Deleted files (see here
http://support.microsoft.com/default.aspx?scid=kb;en-us;136517#top) and does not appear to have any connection with compressed files.
My understanding is that when a file is compressed a compressed file flag bit is set. When Windows accesses the file (the entry in the file system index that is) it checks the flag bit and if the bit is ON the file is then decompressed before being accessed (the flag bit is turned OFF) and remains decompressed until the Last Accessed time equals or is greater than the number of days set in the Disk Cleanup option for compressing files and Disk Cleanup is run. Files can be compressed in other ways as well of course.
I understand that compressed files are not stored in any special folder, they are compressed in situ and the only change to the file index is that the compressed file flagbit is turned ON
Unfortunately I have not found a MS KB or similar article to verify the above but I am looking...