I have to +1 Defraggler as well, having it run daily (overnight) after an automatic CCleaner run works well.
Just to give it a go, I installed PerfectDisk and had it analyse my drive:PerfectDisk Free Edition
That said, though, what does PD do differently than Defraggler/<other defragmentation tool here>? Defraggler does boot-time defrags as well, if you tell it to, of normally-locked Windows files, and it optimizes the drive's free space, and can even do built-in error checking (sometimes the filesystem "loses" freespace somehow during an intensive defrag, and this "reclaims" that space
). It also does SMART monitoring, and tells you in simple terms if your drive is healthy or not. And obviously, it can do just one directory/file/whatever, or just a selection of them. Oh, and a basic scheduling system that uses Task Scheduler. I'm just looking for a comparison I suppose.