How do I remove pre-installed software?

Welcome to Dell Community. :emotion-15:

If you are wanting to remove NIS (so you can install a different anti-virus) reboot into Safe Mode:

Restart your computer. When the computer starts you will see your computer's hardware being listed. When you see this information start to gently tap the F8 key repeatedly until you are presented with the Windows Vista Advanced Boot Options.
Select the Safe Mode option using the arrow keys.
Then press the enter key on your keyboard to boot into Vista Safe Mode.
When Windows starts you will be at a typical logon screen. Logon to your computer and Vista will enter Safe Mode.

From Control Panel/Programs and Features:
Scroll to Norton Internet Security, select and choose the 'Remove' option

Once removal is complete, reboot normally if no other Norton/Symantec products are present on your machine(e.g. Ghost)
 a. If other Norton Products are present repeat the above process and also remove(if present) LiveReg and Live Update
 b. Download the NRT(Norton Removal Tool)
https://www-secure.symantec.com/norton-support/jsp/help-solutions.jsp?docid=20080828154508EN&lg=english&ct=united+states&product=home&version=1&pvid=f-home

Save the file[Norton_Removal_Tool.exe] to your Desktop    
     
 c. Double click the Norton_Removal_Tool.exe to remove any remnants of Norton Internet Security.
 d. Reboot the system normally twice after the removal process is complete.

Note: If other Norton/Symantec non security products are in use besides NIS(e.g. Ghost, Save and Restore))and you do choose to use the NRT in addition to removing NIS via the Control Panel, you will have to reinstall that application.
 
* You will be using the Windows Firewall, rather than Norton, when this is done. Therefore, check the Control Panel's Windows Firewall to make sure the Windows Firewall is enabled.

Let us know if you have any questions regarding the installation of a new anti-virus.

Hi... Have not got norton... But these things are normally standard..... Removal normally involves the use of a removal tool ...as it is not activated the add and remove programs may be all that is needed.... Depends on what version you have 360 etc... http://lmgtfy.com/?q=norton+removal+tool PS Symantec are the creators of the norton product range , as such only get a removal tool from them.

Although AV software has not been activated, it is usually a good idea to follow the uninstall with the removal tool to lessen the possibility that there may be upsell prompts remaining on the system.