I tried out Defraggler also and I am sorry to say, even though it has a interesting concept, the program, version 1.1.44, has some problems on my XP SP2 system, 80 GB HD. After analyzing, it found and listed 3.2 GB of fragmented files, ran defrag and the program self aborted at 49% defragging files, analyzed and ran the defrag again, the program got to and "hung" at 18% defragging the free space, for over an hour, before I aborted the procedure. Once again, I analyzed, the program showed 0 fragmented files. Just for fun I ran the Windows Defragmenter, immediately after, it showed a few fragmented files but hardly enough to bother mentioning.
I did find the analysis was quick, and defragging individual files and smaller groups of selected files, Defraggler, seemed to work just fine.
Anyway, I see that there is a debug setting for the program. In a week or so I will test it again and send a report if needed.
Thank you for hearing me out,