I think this is what you mean , you will have to go into tools and options on the firefox browser, change save files to too ask where to download and you can tell it where to put it, if this is not what u mean then you will have to go into the control panel and set up the applications that open certain software, start button, control panel,add and remove programs on the left hand side click on ,set program access and defaults and look for winrar or what is making it open in html and that should be you , and then bobs your uncle if not any of these then , ask again exactly what you mean and i will see if i can help you cheers
ian