In Windows XP you had the option to analyse a disk drive you wished to defragment without carrying out a full disk defragmentation. Looking at the Windows Vista Disk Defragmenter GUI at face value I thought this feature was left out. After some research, I found that this this feature has been included but you will be forgiven for not knowing where it is. Fortunately, using the command line tool does allow you to analyse a drive. It is as simple as typing the following:
1) Open up Command Line tool.
2) Type the following: defrag –a <disk drive letter>
3) Press enter and you will see the following: