Translation of Schadstoff

Can you translate: Are you using the firefox browser? Install this tool in your browser window. The ones I suggested the other day are the most useful ones, because we would use it for generic terms which differ from Spanish.
I really value honest comments, and I am a believer that it is the only way that the social community system works, so as to know whom you can trust on both sides. Programmers did a great job if you were asking me.
I want learn Spanish because of my girlfriend from Guatemala. She is from Latin America. And of course I want improve my grammar too. I like to hear it, but speaking is still hard. Hasta Luego.