why don't you simply uninstall it with the Win interface?...AVG is unlikely to leave anything disturbing on your machine once removed...
Actually, in my experience of reading about folk with this installed, usually the reverse is true.
AVG can (and does) leave a lot behind.
Uninstall from the control panel first, for sure.
Uninstall components (like the linkscanner, the firewall,) if they remain, from the control panel if the entry is there, or from the browser add-on menu.
Then run the tool.
Running it can do no harm. On the other hand, it may do a fair bit of good.