Google Toolbar for Firefox

I am not able to proceed further after installing the Google Toolbar for Firefox. After the mandatory browser restart, a dialog window pops up, asking for preferences, but doesn't respond to any inputs (there is a cute warning asking you to *really* read the fine print, but I am in no mood right now to appreciate such things). I need a way to get rid of this extension pronto to resume using Firefox or to fix the problem. I am posting this from Opera, in case anyone is wondering.

Update: Turned out to be a permissions problem. Started Firefox as sudo, dismissed the preferences dialog, then reverted to being a normal user.