Several new contenders have entered the fray since I last reviewed this category so I was delighted when regular contributor Eric Santucci offered to do a comparative review  for me. Eric looked at four freebies as well as a commercial defragger for comparison.
He found that all the programs improved disk performance but the gains were modest and the differences between products small. The result is not surprising; with modern hard drives the benefits of defragging are much less pronounced than a few years ago.
Eric’s personal choice was JkDefrag . I understand that choice but would tend to prefer Diskeeper  Lite due to its proven track record of reliability. Diskeeper’s attraction is further enhanced if you look at some of the tweaks you can make – see item 5.1 for details.
And here’s another reason to use Diskeeper: Eric tested Diskeeper Lite V7, the version that is most widely available for download but there is a neat way to get Diskeeper Lite V9. It forms part of Intel’s large (89MB) Desktop Utilities V220.127.116.11 package which is available from the Intel site . When you unpack the file you’ll find Diskeeper V9 Lite in the folder../3rdparty/Diskeeper/. Make sure you don’t accidentally run the setup.exe file that’s in the root folder – that’s the Intel Desktop Utility setup program.
Neither the read-me file nor the License Agreement prohibit downloading and using this program on a single computer so it appears to be a perfectly legitimate way to obtain the program.