In Firefox's Firebug add on you can modify the current page HTML and styling. I think you can do the same with Chrome's in build developer tools accessed from, unsurprisingly, the tools menu.
If you know the code you don't want to run just alter that onclick or whatever. Note thought that if you refresh the page or navigate away you'll lose your modifications.
If you're paying for your web hosting then you are probably entitled to some support from them. I'd ask them to investigate your issue - you may even be helping other users using their web hosting with a similar issue.