Norton is a resource hungry software that very much fails when compared to AVG, Kaspersky, AntiVIR, Avast, and a few other free for home use versions. For a retail product you should have a look at Trend Antivirus Plus Antispyware 2007 that combines adware/spyware reomvers along with the antivirus protection. http://www.trendmicro.com/en/products/desktop/tav/evaluate/overview.htm
Norton itself falls into the low catagory along with McAfee. Most of the time Norton is mentioned here is when someone has discovered something that simply slipped right past it.