> ... Hrútur hefði þungt af fengið Kotkatli ...

Wonderful example of what seems to us a very odd word order:
both <H. hefði þungt fengið af K.> and <H. hefði þungt af K.
fengið> would be more natural to us.

> Kjartan kvaðst eigi vilja gera í mót vilja föður síns, það
> er hann mætti við gera, en kvaðst vænta að þetta mundi
> betur takast en hann gat til.

> Kjartan stated for himself not to want to do against his
> father's desire, that which he would be able to do with,
> but stated for himself to hope that this would better
> begin when he got to. (?)

> Kjartan said he would not want to behave against his
> father’s will, that which he was able to do, but said he
> expected that this would happen better than he guessed.

> Kjartan declared-of-himself not to want to act against
> (the) will of his father, that which he might prevent (act
> against), but declared-of-himself to hope that this would
> turn-out better than he (ie his father) supposed (geta,
> Z.ii.1).

'To prevent' is the gloss for <gera við e-u>, with a dative
object, but <það> is nom./acc. I think that we're dealing
with <við> 'respecting, regarding' (II.6 in Z.) or something
similar: that would give 'that he could do [something]
concerning', meaning that he didn't want to act against his
father's wishes insofar as he could help doing so. I note
that Icelandic Online says that in the modern language <gera
við e-ð> is 'to mend, to fix something'; this would fit
rather well, but I've not seen any evidence that it's old
enough. Perhaps it developed out of this sort of usage.

It's a tough call, but I'm inclined to think that 'expect'
fits the context better than 'hope'; I get the feeling that
he's pretty confident.

> Ásgeir hét maður og var kallaður æðikollur.

> A man was named Asgeir and was called eider-duck-head.

> A man was named Asgeir and was called eider?crown.

> (There) was a man called Ásgeirr and (he) was called (a)
> duck-head.

It's actually <œðikollr>, from <œði> 'rage, fury; madness,
frenzy'. Presumably he was a real hothead.

> Hann bjó að Ásgeirsá í Víðidal.
> He lived at Asgeirsa (the-god-spear ?) in Vididale.
> He lived at Asgeir’s river in Wide Dale.
> He lived at Ásgeirr’s-River in Víðidalr (Willow-Dale /
> Wide-Dale?)

Apparently it's 'Willow Valley'. According to Landnámabók
(Þórðarbók ms.):

At vetri kom Ingimundr í dal þann, er var víði vaxinn, ok
kallaði þat Víðidal ... .

'Vatnsdœla saga', Ch. 14, is even more explicit:

Þá mælti Ingimundr: "Sjá dalr er mjök víði vaxinn. Köllum
hann Víðidal ok hér ætla ek líkast til vetrsetu."

To be <víði vaxinn> is to be overgrown with willows; see
Zoëga s.vv. <vaxinn> (2), <vaxa> (2).

> Hann var son Auðunar skökuls.

> He was a son of Audun car-pole (what's a car-pole?).

> He was a son of Audun car-pole (I have no idea what that
> means).

> He was (the) son of Auðunn wagon-shaft (like a
> bean-pole?).

Yes, 'tall and slender' would be my first guess, though
there's always the possibility that it refers to some
specific event in his life, in which case the meaning's
probably unrecoverable unless the incident is recorded
somewhere.

Brian