Different methods to uninstall Service Pack 2 from Windows XP:

Method 1:

1. Open Control Panel and navigate to "Control Panel\Programs\Programs and Features".
2. Select the service pack 2 and click uninstall.


Method 2:

1. Open Command prompt in admin mode.
2. Type the following command to uninstall the hidden files,

         c:\windows\$NtServicePackUninstall$\spuninst\spuninst.exe

This step will allow to uninstall the SP2 completely.

Enable Or Disable a particular feature in Windows Feature (Win 7,8):

Inorder to disable or enable any Windows Features, the manual method requires the following steps,

1. Click Start and type "Trun Windows features on or off".
2. Press Enter and do select the particular feature that has to be altered.
3. Finally restart.


If Performed through command prompt, following are the steps required,

1. Open command prompt in admin mode.
2. Type the command and press enter to get the details of all the features in the system.

               dism /online /get-features | more

3. Type the command to enable a particular feature,
     
              dism /online /enable-feature /featurename:<feature name>

   Example: dism /online /enable-feature /featurename:TelnetClient

4. Type the command to disable a particular feature,
     
              dism /online /disable-feature /featurename:<feature name>

   Example: dism /online /disable-feature /featurename:TelnetClient