Ya, Linux is great for netbooks or machines that are almost exclusively used for web surfing.
I'm not a big fan of Norton products. They're too "consumer grade"....the program treats you like a complete idiot, uses tons of computer resources, and it used to crash the computer if it "popped up" while I was using any full-screen program. Plus, they score only average for virus detection.
AVG is free, stays out of your way unless there's an immediate problem, and uses only about 1MB of memory running in the background(norton used to take 70-80mb of memory).