i'm no fanboi of TalkTalk, but I see nothing in your threads and links that would cause me undue worry.
The threat is a possible threat only, just like hammers are possible murder weapons.
The webmaster thing has been dealt with as far as I can see (I doubt very much that there is a job title at TalkTalk called Webmaster
A web form allows interaction with the database without giving database access to the form user. The form gives a code which when used by the OCE in their special form presents detailed database information on that form or report.
The TV Ads are not personalised or directed specifically at you, they are directed at everyone who logs in.
You can argue that it only targets those who log in, but that's not the same as being personalised, or you could argue it was personalised as it was directed at only people with working eyeballs. Jus because an ad isn't directed at everyone in the world doesn't make it personalised.
Yes, it's annoying, but it is not a legal problem. It's an aesthetics or customer service problem. As you attempted to attack the ad via legal means, that is the response you got. If you had attacked it from an aesthetics/CS viewpoint you might have gained more traction.
That you can't get to the right page to pay your bill is your only relevant grievance. I also distrust DD and you have every right to be able to pay on the day of your choosing, after checking all the details are correct. DD screws up so often the only fair assumption is that they purposely "make errors" hoping you wont notice.
Not sure you will take my advice, as I know how it feels to head down an stubborn path, but if you can, drop the other issues and focus on the bill payment issue. You need some kind of solution before it goes as a default on your credit history
In theory, theory and practice are identical.....in practice they aren't!