The following tutorials use the Disk Defragmenter:
1. On the Start menu, select the program-> Acessories -> System Tools -> Disk Defragmenter
2. Select the drive containing your windows files (eg drive C), by default windows installed on drive C
3. Click the Analyze button, wait until the windows do an analysis of the files on your hard drive. If any files are not fragmented, then the box to do the defrag dialok. Press the defrag, this process takes about 1 - 4 hours depending on capacity hard drive defrag
This defrag process should be done once a month or two month when many do a lot of file changes on your hard drive.
References: Artikel Komputer