When I tried to download a torrent of a TV show I'm watching there was some codec I had to instal so I could watch it. So I downloaded it (unfortunately) and apparently it changed my Firefox homepage to startsear.info. I am unable to change the settings back to my original home page because it resets every time I exit Firefox. Not sure what's with IE, the one my father uses for paying bills. I'm really an amateur so please guide me through this or if there is some special antivirus which can remove this. Please help me!
I'm using Windows 7 if that information is helpful.