I must admit that disk defragementation is one of the many fields I neglected in the past. Usually, I only use a defragmentation tool when the performance of a machine is going down. Depending on the size of the hard disk, this can be a very tedious process and will slow down the computer even more. It makes much more sense to run a disk defragmentation tool in the background at certain scheduled times. This way, the hard disk structure will not get too messy and defragmentation will be done fast. If you have many machines in your network, you need a tool that you can manage centrally.

WindowsITPro has a good review of three popular tools for Windows: Diskeeper 10, PerfectDisk 7.0 and Defrag Manager 4.0. The editors choice is Defrag Manager:

Defrag Manager excels thanks to its user friendly features-particularly, its simple deployment architecture, its intuitive console program, and its support for scheduling by AD OU or by groups that you define. The Advanced Mode Boot CD’s ability to perform a complete offline defragmentation uniquely accommodates difficult situations. The CLI defrag program adds the extra flexibility you need. This combination of ease of use, simplicity of design, and broad capability make Defrag Manager my Editor’s Choice.

If you are planning to use a defragmentation tool in you network, I recommend reading the WindowsITPro article. You will learn a lot about this subject.