Unusual CPU Activity and Slow Internet Fixed By Uininstalling

For some reason, Norton IS2010 was using 50 percent of my cpu usage, even after I disabled automatic scanning and even the firewall and antivirus itself. My cpu temps in just over an hour raised to around 50c

I uninstalled the program and reinstalled Eset SS and my temps very quickly went back to normal, not to mention my internet speeds increased dramatically.

I have a fairly good computer, E4700 and 4 gigs of ram. I just don't see the need for the program to be so cpu intensive....

Any idea what is causing this to happen?