Steps:

• Click "Start"
• Click "All Programs"
• Click "Accessories"
• Click "System Tools"
• Click "Disk Defragmenter" (Click Example: 1)
  
• Click "Defragment" (Click Example: 2)
  

Example:1

Example:2

Note: Depending on your systems speed this may take several minutes.

Optional: Check your drive for errors.

• Double Click "My Computer"
• Right Click on "C:\"
• Click "Properties"
• Click the "Tools" tab
  
• Click "Check Now" under Error-checking (Click Example: 3)
• Place a check mark on "Automatically fix file system errors" (Click Example: 4)
• Click "Start"
• Click "Yes" The next time you start your computer the Check disk will run.

Note: The Error Checking cannot be performed on C:\ right away.
Your computer will need to be restarted in order for the check disk to run.

Example: 3

Example: 4