Many, many people are very displeased with the new, so-called improved Norton 2007...
If... IF you can get your money back (Ha Ha Ha Ha Ha as far as dealing with Symantec and returns is concerned!)---
Try Avast Professional
avast! antivirus software - computer virus, worm and Trojan protection by ALWIL Software
Many folks find it to be superior to Norton Internet Security (any version) and it uses far less of your resources.
I gave up with Norton (except for comparison testing about every 6 months) almost 2 years ago. Avast Pro has never caused a problem... ONCE you have it set up !