There's some very good advice in this thread, & I know it's a bit old [the thread, I mean], but I thought I'd add my own advice.
Firstly, anyone using windows should go
here & follow the instructions on modifying your HOSTS file. I won't try to explain it as that page does a better job of it than I could.

Secondly, if you want more security/features than IE but still want the look/feel of IE because you don't like Firefox, try
Maxthon. It uses IE's engine [although there is the option to use the Gecko engine, which I *think* is from Firefox?], but has a whole heap of features/stuff that IE doesn't have but should. Again, it's site can tell you about it a lot better than I could, but suffice it to say that I don't ever see any particular advert [of *any* kind] more than once if I don't want to, & it blocks quite a lot by default already.
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BatmanX - nice job on migrating the forum to different software, I've seen quite a few that have managed to get borked completely whilst doing that, so kudos to you.
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