Can't un-install Norton Anti Virus

[nuttychix]

my free trial from Norton has run out, so i am trying to uninstall Norton from my Laptop (vista) I started to install AGV (free version) but it told me to stop as Norton was on an need to be uninstalled first.
Havin trouble removing it..keeps telling me NOT ABLE TO REMOVE. you are trying to
uninstall a program that is required for other symatec products to run on your pc. You are unable to remove this product at this time.....i have been through the list of programs and have removed all symantec products...any ideas please?
pls bear in mind im not very technical so not too much jargon please.
Thanks

[dabees]

Use this link to get the Norton removal tool.

http://service1.symantec.com/Support/tsgeninfo .nsf/docid/2005033108162039