Windows 7 has a cool feature that allows you to set a time to automatically defragment your primary hard drive. This process runs quietly in the background.
Step 1: Open the Disk Defragmenter from the Start menu by typing “disk defrag” in the Run box. You can always navigate to the actual program from Start by selecting All Programs > Accessories > System Tools > Disk Defragmenter.
Step 2: Click the “Configure Schedule” button to open up the window where you can pick a desired time to defragment your computer.
Step 3: Now click on “Select disks…” to see a list of disks available for defragmentation.
Step 4: At the bottom of this window, make sure the “Automatically defragment new disks” option is checked.
Step 5: Choose OK in both open windows, and close the Disk Defragmenter.
Having all your new hard drives defragmented will take some work from you. Hopefully these steps will point you in the right direction.
Source: cnet