Suggestion
Dear El Reg,
I presume you doen't host your own adverts - or at least not the banners and inserts. I believe you're using a third party.
Could you not implement a process where we could directly complain about shit adverts to both you and them. Some of them are badly coded, and start opening all over the screen - some auto-play music (though I've not seen one of those myself). When I've complained in the past the ads have hung around quite a while, and make the site quite unpleasant to use. At some point I'm going to get pissed off and just put on adblock, and then I'm harming your revenue.
The problem is that the excuse of "it's not our advert" starts to wear thin after a while. As far as the user is concerned it's your site, so it is your advert. So you should care about the harm it does to your reputation more than some random ad-slinger will. Because, obviously, it matters more to you. I've been a forum mod on a non-techy site, who had exactly this problem, and people simply would not accept that it wasn't the site's fault.
I can see both sides of the argument, but the problem is that the rogue adverts work, as well as really pissing people off. So in the short term, the advertisers have an incentive to do it. Even though in the long term it harms them just as much as El Reg. The best way I can think of to deal with this is to allow the users a method to complain that lets the advertisers know directly that they're pissing off the customers (in this case both the readers and El Reg). That would also be useful info to have in contract negotiations, or as an excuse to allow you to directly block adverts until they're fixed.