to answer your question there is no "best" just like there is not "best" car alarm or home alarm.
just like the best form of protection against AIDS and std's is abstinence the best protection against viruses, trojan, hackers and spyware is to NOT put the laptop/computer on the Internet at all except for software updates only.
I have a terminal at home that never touches the Internet. I use it for school and storage of personal data. If I need to transfer anything over to the internet, I use an external 200GB drive to back it up on then move to my laptop which is live on the internet.
I reformat my laptop every year, save all programs and back up all files to the 200Gb drive just in case. A system on today's internet that is not behind a hardware firewall is always at risk no matter what you have on it....the least you can do is put a router inbetween you and your dsl and/or cable modem and enable NAT and turn on alot of filters and block ports..etc.
I've used norton, symantec, mcafee doesn't matter..they are all the same. You have to take better caution and not rely on the software as the solution that's all.
the internet is 24/7 now where as only 10 years ago most of us used dial up where you actually had to dial into the internet and download trouble.
now you can just turn on a pc and it's infected just like that if you are plugged directly into a modem. It happens.
good luck.