it is important that you run a disk defragmentation and a disk clean up every week or every month depending on how much you use your computer,
to do this simply follow the simple instructions below

windows xp

disc cleanup
•Click Start, point to All Programs, point to Accessories, point to System Tools, and then click Disk Cleanup.
disc defragment
1.Open My Computer.
2.Right-click the local disk volume that you want to defragment, and then click Properties.
3.On the Tools tab, click Defragment Now.
4.Click Defragment.

Windows vista and 7

disc cleanup
1. Open the Start Menu, click on All Programs, Accessories folder, System Tools folder, and Disk Cleanup
2. Select the drive that you want to use Disk Cleanup on, and click on OK
NOTE: You will not see this window unless you have more than one drive or partition on your computer.
3. You will now see a progress bar After this has finished continue with the next steps
4. To Delete Unnecessary Non-System Files
A) Check the type of files box that you want to delete, and click on OK
B) Click on the Delete Files button
C) The files will be deleted and Disk Cleanup will close
5. To Delete Unnecessary System Files
A) Click on the Clean up system files button
6. To Open Programs and Features
NOTE: This will open the Programs and Features window where you can uninstall programs. You could also do this by opening Programs and Features in the Control Panel.
A) Click on the Clean up system files button, and repeat steps 2 and 3
B) If prompted by UAC, then click on Yes
C) Click on the More Options tab
D) Click on the Clean up button under the top Programs and Features section
E) Click on OK
F) In Programs and Features, select any program that you want uninstall
7. To Delete All but the Most Recent System Restore Point
A) Click on the Clean up system files button, and repeat steps 2 and 3
B) If prompted by UAC, then click on Yes
C) Click on the More Options tab
D) Click on the Clean up button under the bottom System Restore and Shadow Copies section
E) Click on the Delete button to confirm the deletion
F) Click on OK
G) Click on the Delete Files button
H) The files will be deleted and Disk Cleanup will close

disk defragment
1. Open the Start Menu, and double click on to expand All Programs, Accessories, System Tools, and click on Disk Defragmenter
2. To Analyze a Disk
NOTE: This will analyze the selected disk to see what percentage fragmented it is. If the number is above 10%, you should defragment the disk
A) Select a disk, and click on the Analyze disk button
3. To Defragment a Disk
NOTE: Disk Defragmenter might take from several minutes to a few hours to finish, depending on the size and degree of fragmentation of your hard disk. You can still use your computer during the defragmentation process
A) Select a disk, and click on the Defragment disk button
B) You will now see the disk being defragmented
NOTE: You can abort the defragmentation of the selected disk at anytime by clicking on the Stop operation button
4. When finished, click on Close