I also bought a new laptop with Norton 2007 (60 days trial) loaded.
I decide to keep the norton since it came with the laptop (na awuf thing).
Unfortunately it didn't keep my system entirely safe.
Atimes it would detect a virus but wouldn't have the ability to quarantine or flush it from my system.
I eventually had to remove Norton after some viruses sneaked in along with some homepage hijackers.
I went back to Kaspersky I was very comfortable with on my older system.

Try the
REMOVEIT I recommended if you're not yet ready to remove your current antivirus . (Its not yet compatible with VISTA)