Okay so I got this DB radiant quest that seems to endlessly loop and give me money while I kill people, in theory it's all well and good but is there any way to complete this quest completely so it doesn't automatically reset and sit in your quest tracker forever?

I wanted to be done with the DB and never look back, however this is now a problem because I can't seem to get rid of this quest at all, why Bethesda, why must you force my Quest Tracker (It doesn't qualify as a Journal) to be cluttered with quests I'll never do anymore, with no way to get rid of them!

This whole "Auto objective" nonsense is becoming a major pain in the ass, more so when it's something that really shouldn't be a problem in an ES game.
Atleast the Thieves guild have the courtesy to make you talk to them to trigger their repeating quests, you don't get a choice here, it automatically starts the moment you finish a previous contract.

Yeah...the quest never ends.

Excuse me, just getting fed up with people complaining about perm. quests, but it's a journal. Do you know what a journal is? It's a record of events. You can't 'remove' events once they happen. Just ignore them. The Dark Brotherhood thing never dissapears, just ignore it in your list and don't track it.

No, it's a problem, and a rather annoying one, also what we have in Skyrim aren't Journal's at all, I'd call it a Quest Tracker, which makes having unwanted quests that much worse.
Now what Oblivion and Morrowind had were Journals, Skyrim's certainly doesn't qualify for any sort of Journal I know of, it's lazy (That's putting it nicely)

The Skyrim journal had to be dumbed down for the casuals, we don't want them to think that much do we?

Simply ignore the quest. Nothing you can do about it.