One of the best features of Windows ME, XP, or Windows Vista is the System Restore option, if you need disk space you should disable System Restore. It  will clear all old system restore points and free many gigabytes, then reenable it after the system is clean. New system restore points will be automatically created by Windows again, or you can create one hit start menu->programs->acessories->system tools->system restore->create new restore point.

Follow the instructions below to disable System Restore

Disabling System Restore on Windows XP 
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1. Right-click the My Computer icon, and then click Properties.
2. Click the System Restore tab.
3. Check "Turn off System Restore" or "Turn off System Restore on all drives" 4. Click Apply. 
5.  When turning off System Restore, the existing restore points will be deleted. Click Yes to do this.
6. Click OK.
7. restart the computer and follow the instructions in the next section to turn on System Restore.

To turn on Windows XP System Restore: 

1. Right-click My Computer, and then click Properties.
2. Click the System Restore tab.
3. Uncheck "Turn off System Restore" or "Turn off System Restore on all drives."
4. Click Apply, and then click OK.

IMPORTANT NOTES: 

You must be logged in as an Administrator to do this. If you are not logged in as an Administrator, the System Restore tab will not be displayed. 
Turning off System Restore will clear out all previous restore points. 
To turn off Windows XP System Restore:

NOTE: These instructions assume that you are using the default Windows XP Start Menu and have not changed to the Classic Start menu. To re-enable the default menu, right-click Start, click Properties, click Start menu (not Classic) and then click OK.


Disabling System Restore on Windows Vista
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To turn off Windows Vista System Restore:

1. Right-click the Computer icon, and then click Properties.
2. Click on System Protection under the Tasks column on the left side
3. Click on Continue on the "User Account Control" window that pops up
4. Under the System Protection tab, find Available Disks
5. Uncheck the box for any drive you wish to disable system restore on
6. When turning off System Restore, the existing restore points will be deleted. Click "Turn System Restore Off" on the popup window to do this.
7. Click OK
8. When you have finished, restart the computer and follow the instructions in the next section to turn on System Restore.


To turn on Windows Vista System Restore: 

1. Right-click the Computer icon, and then click Properties.
2. Click on System Protection under the Tasks column on the left side
3. Click on Continue on the "User Account Control" window that pops up
4. Under the System Protection tab, find Available Disks
5. Place a checkmark in the box for any drive you wish to enable System Restore on
6. Click OK


Disabling System Restore on Windows ME 
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1. Click Start, Settings, and then click Control Panel.
2. Double-click the System icon. The System Properties dialog box appears.

NOTE: If the System icon is not visible, click "View all Control Panel options" to display it.

3. Click the Performance tab, and then click File System.
4. Click the Troubleshooting tab, and then check Disable System Restore.
5. Click OK. Click Yes, when you are prompted to restart Windows.


To enable Windows Me System Restore: 

1. Click Start, point to Settings, and then click Control Panel.
2. Double-click System, and then click the Performance tab.
3. Click File System, and then click the Troubleshooting tab.
4. Uncheck Disable System Restore.
5. Click OK. Click Yes, when you are prompted to restart Windows.

 
