The accessibility of non-"Internet Explorer" applications to that content setting was only introduced in Vista, so you'll need to purchase either that or Windows 7 for Firefox to know what the settings are. Alternatively, I suggest switching your DNS servers to [http://en.wikipedia.org/wiki/Opendns#Servers OpenDNS] and [https://store.opendns.com/get/basic signing up for an account] to turn on their content filtering for '''every''' application that can connect to the internet. This is free by having ad-supported search suggestion pages when you do a typo in the address bar. It also has [https://www.opendns.com/start/ paid accounts] if you don't want the ads. They have [http://www.opendns.com/support/videos video tutorials] and [http://www.opendns.com/support/article/251 frequently asked questions] articles