Defraggler

Running a defrag on your computer re-arranges where everything is on the hard disc, the files are re-arranged so that ones that are likely to be used together are close by for increased speed when using your computer. Defraggler by Piriform improves on the defrag software provided by Microsoft, it will tell you how fragmented (unorganised your hard drive is) from a quick analysis allowing you to decide if you need to run the defrag.

Best of all defraggler is free! So why not give it a go and see if it can speed up your computer.

(Download at http://www.piriform.com/defraggler/download/standard)