I'm not really talking about Nazeem, he's supposed to be a dike, I think. I'm talking just utterly poorly written shlock, that you can't even understand how it got off the writing table, much less made it into the completed game.

For me I think it's Captain Lonely-Gale's:
"Folks around here call me captain, because I used to be a sailor!"

"I work for Belethor, at the General Goods store!"

I. FREAKING. KNOW.

http://www.youtube.com/watch?v=F2vejpMhMl8

Jump to 1:10
It's not the dialog itself, but the way it's read. If you happen to know what quest that guy just completed for all of that dialog to trigger, then yes, some of the dialog is REALLY stupid (specifically the "my wife is dead. DEAD!" guy).
Other than that, the "oh so you're interested in my potions and ingredients?" or "oh so you're an alchemist then?" lines are pretty dumb. That's like if I were to go to the super market, say I want a flat-screen TV and then the seller either says "Oh so you're interested in my TVs then?" (no [censored] [censored], you little [censored]) or "Oh so you're an electrician then?" (tf?)

Should've gone like this:

Dragonborn: So your wife was a vamp--
Thonnir: /PUNCH. MY WIFE IS DEEEEEEEEEEEEAD.

some people call this junk, me, blah blah blah yadda yadda....

Really, anything I have to hear 5 bazillion times in order to advance my game.

I used to be an adventurer like you....I can't even bring myself to finish it.

All of clavicus vile's dialogue

All of Barbas' dialogue

Not so much the dialogue, but the voice acting was so unbelievably cringey it made me want to throw the game out the window.

I mean did they actually pay those guys to do the reading? Feels like they just got some randomers from the street to put on poor accents and do it!

I agree with this one, it's like way to sell your merchandise... I remember once one of them told me their stuff was junk and i was like "Oh this is just junk? [censored] that then," and I exited out and went to another vendor.

I don't claim to be the best smith...
Who would ever self-deprecate like that?

Everything Mjoll says.

"Everything's for sale my friend. Everything. If I had a sister I'd sell her in a second."

Belethor sets a record for cluelessness by repeating variations on the same distasteful joke to his female customers.

...

Please tell me there's a mod where I can sacrifice Belethor to Boethiah and Sigurd inherits the General Goods store?

Lydia's sarcastic "I'm sworn to carry your burdens." I wasn't all that sad when she died.

And, yeah, Belethor's a dike. "Do come back" is pretty high on my irritating list.

I'll go with Thonar Silverblood, "My wife, they killed her." sounding like he was describing an extraordinaly dull day at the office

I'll third this. My main problem with it is if I hear a merchant say that, I'm leaving because it means he/she has too high a regard for their stuff and will charge to much for it.

Next is Babette. Whoever the girl is reading the part sounds like she is reading the part, especially when she tries to do an evil laugh. She cannot do evil.

When it comes to pure dialogue (not one-liners or comments), much of the Thieves' Guild questline annoyed me. I like to be able to at least choose between two different wys of saying basically the same thing - now it feels like they put words in the mouth of my character that doesn't fit her at all. (At some point I had to say something that implied that I knew nothing of magic and powers, I'm a thief, which is a pretty weird line for a thu'um-using Dragonborn who might very well be a mage as well, as far as the writers know.)

The proposal dialogue. It makes me want to vomit.

Anything Nazir says 100 times! You'd think Three Dog would have done better

I used to be adventurer like till I ....................... I'm like really!? Do you know how many arrows and swords I've taken! Take it like a true Nord and quit your whining!

do you get the cloud district very often?

you smell like death

im swoooooorn to carry your burdens

Ouch. My vote goes definitely the "Oh no no no, this is so wrong" guy.

Feels a bit like speaking to a dentist without the empathy?

Hehe, I have to agree with this one. Same goes with the "So you wish to master the acrane arts..." or "I knew you were a mage..." (or something like that, can't remember now) when all I want to buy is a daedra heart to smith some armor.

Yes! And the most annoying line of hers to me is "So you're interested in my potions and ALACAMEE reagents?"

That's how she says it! And while it may be cute for a little girl to say it, she's a 300 year old vampire and most certainly would have learned the correct pronunciation by now!!

The merchants in Whiterun. I spent so much time there my first playthrough I just want to murder them all in the face.

The stupid cliched arrow to the knee thing. A arrow to the knee won't stop you adventuring!

Everything single thing Brynloff says.
Every single thing every one of the TG says. It's all done in such a sickening, revolting, over sentimental way, every freaking little word! They act like talking about hurting people and robbing them is so important and lovely.
The tone is save my cute farm, feed the bunnies, the words are rob, steal, demand protection from shopkeepers.
It's like they don't know they are filthy scumbag criminals. Every single line is delivered like they are talking about a cute farm with fields of flowers and bunnies.
If you did'nt know what was going on and just heard the tone, you'd think they were talking about a cute farm, that had trouble from raiders or something!

Delvin Mallory, goes from normal to wierd in a flash. He's actually like a borderline normal person outside of the TG.
It's like one minute.
Hello, give my regards to Astrid.
Then completely changes tone from normal to wierd.
Boohoo! the TGs in twouble! We're cursed! Nearly cries, seriously, then, asks you to help them.
It's like WTH?!

The proposal dialogue is wierd.
It's so calml. You'd think you were just buying stuff.

When they won't let you insult people you hate and force soppy and stupid lines on you.

Everything Barbas says.

Every single guard in the game pisses me off they should have used there employees to do voices for the guards. it couldn't be worse than having the same voice.