I too have been having problems with the use of Defraggler. It was taking hours just to do 1% of the defrag.
What I found was an updater on my laptop sending the processing up to 100% using the task manager. After 2 hours of it working and seeing this use most of the processing I stopped it and it made defraggler speed up.
Maybe there is a process stopping your defrag and it could be that. So using the task manager have a look at what is running too high and close it to see if it makes it work more.
