Dunno if this will work, but try uninstalling avg.
Then reinstall, ensuring that the taskbar option is deselected (I'm assuming you can because I have avg, but not the taskbar, and I am usually careful about these "hidden" things they try to slip through)
I think you have to take the "custom" option (or similar) on the AVG install to deselect the task bar.
Many of these free products now try to install various task bars and search bars so I always take the custom option during install and read each window carefully before clicking Next.