How to perform a disk cleanup

A disk cleanup will free up space on your hard drive, and as a side effect make virus and spyware scanning faster, as fewer files must be scanned. Also, some networking problems may be a result of the temporary file folders being too full, and a disk cleanup will alleviate these problems. In conjunction with a disk cleanup, the Internet Options dialog should be used to clean the Temporary Internet Files folder.

To perform a disk cleanup, open My Computer, either on the Desktop or in the Start menu.
Right-click on the icon for your system drive, normally the C: drive, and select Properties on the pop-up menu.
On the drive properties dialog click on the Disk Cleanup button. Disk Cleanup will then calculate the the amount of space you will be able to free, and finally display a dialog that displays the areas where files can be deleted. This will be on the Disk Cleanup tab.
Normally you will want to check all of the checkboxes in the list, but if you are unsure about a particular item, click on its line in the list box, and under Description you will see a description of the item. If this is something you do not want to delete, then leave the corresponding checkbox unchecked.
Click OK. The files will be deleted.
If this Disk Cleanup is being performed on a Windows XP or higher system in conjunction with a scan for malware, and you have reason to suspect more than minimal malware on your computer, perform steps 6 through 8, otherwise skip to step 9.
In steps 6 through 8 you will be deleting all System Restore points but the most recent. Normally you will not want to do this, as you may well need these restore points in the future. However, these restore points can also return malware and viruses to your system, so if you have reason to suspect more than a minor infestation it is better to delete them. (After you have finished cleansing your system, you will want to make a restore point that is free of malware.)
Select Disk Cleanup again on the drive properties dialog. The Disk Cleanup dialog will re-open.
Select the More Options... tab. In the System Restore region click the Clean up... button, then click yes.
Click OK on the Disk Cleanup dialog.
Click OK on the disk properties dialog.

That completes the Disk Cleanup per se, but it is recommended that you also delete the temporary Internet files at this point if you have not recently done so. The procedure for deleting the temporary Internet files is more thorough at removing some files than the above Disk Cleanup procedure.

Open the Control panel.
Windows XP: go to Start and open Control Panel. If you are in category view click Network and Internet Connections, then Internet Options. In classic view open Internet Options.

Windows 2000: on your Desktop open My Computer, and then open Control Panel. In the Control Panel open Internet Options.
In the Internet Options dialog click Delete Files.... Click on Delete all offline content to check the checkbox, and click OK.
On the Internet Options dialog click OK.

That completes the process of cleaning op your disk. Do this regularly do keep your system lean. You should also consider going to Add and Remove Programs to remove any programs you do not need.