So, what is the problem then? if you have both adblock and a antivirus then I don't understand why mediafire was a problem for you after your antivirus "stopped them".
I mean, I am understanding what your saying but what is so hard about opening a new tab and closing the supposed "malicious" page? I'm sure that antivirus stops you from actually getting a virus so essentially all you are seeing is a unwanted page, mine is usually some kind of sports betting thing but it's not a big deal to just close off that page.