In Windows XP and Server 2003, run command for disk defragmenter is dfrg.msc.
In Windows 7 and Server 2008 disk defragmenter can be launched by running the command dfrgui.
These commands can also be used from command prompt.
on December 24, 2011
Run command for disk defragmenter
it is useful
or defrag if you want to defrag right from cmd