You don't need to defrag the system reserve but if you want to anyway there is a program called auslogis disk defrag that lets you defrag system reserve

Defrag

depends on the OS, but for most it is :

defrag <DRIVE>

example:

defrag c:

No! In fact, it's best that you're NOT online while doing a defrag. Anytime defrag hits a part of a hard drive where the information is changing, defrag restarts doing that portion of the drive. While on the Internet, your PC is constantly sending and receiving files and changing what's on the hard drive. Your defrag will take a lot longer.

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