Norton Replacement

I'm sure a lot of people out there agree with the fact that Norton AntiVirus is a RESOURCE HOG. Can anybody suggest to me a replacement software package that is just as good (or almost as good) and most importantly easier on the system?
My startup times suffer hugely from Norton. Even more annoying are those multiple instances of LuCallBackProxy.exe at startup and at other random moments when updating the databases. They seriously kill my memory usage and CPU cycles.
If it were up to me, I'd more than likely run without one, 'cause I'm fairly confident in identifying what should and shouldn't be existing on my system, but sadly, I can't say that for the rest of the people using this PC.
Thanks for the help in advance...
Signed... Desperately In Need.
My startup times suffer hugely from Norton. Even more annoying are those multiple instances of LuCallBackProxy.exe at startup and at other random moments when updating the databases. They seriously kill my memory usage and CPU cycles.
If it were up to me, I'd more than likely run without one, 'cause I'm fairly confident in identifying what should and shouldn't be existing on my system, but sadly, I can't say that for the rest of the people using this PC.

Thanks for the help in advance...
Signed... Desperately In Need.