Here’s my translation

Alan

Bolli kvaðst hafa á vikið um sinnsakir og kvað hana hafa ekki mjög á tekið:
Bolli declared-of-himself to have broached (vekja, Z5) (it) for this once (see under sinn, um sinns sakir, Z1) and declared her (hana is the object of kveða) to have not much taken to (it) (ie it did not appeal to her, read: was positively icy about it):

"Vænti eg þó að Ósvífur muni mestu um ráða þetta mál."
“I expect nevertheless that Ósvífr will mostly deliberate (ráða um) concerning this matter.” (ie the decision will be mainly his)

Ólafur kvað hann með mundu fara sem honum líkaði.
Ólafr declared he (Bolli) would handle (it) (manage the matter, lit: go with, fara með, Z18) as (it) pleased him (Bolli).

Eigi miklu síðar ríður Bolli heiman og með honum synir Ólafs, Halldór og
Not much later Bolli rides from-home and with him Ólafr’s sons, Halldór and

Steinþór. Voru þeir tólf saman. Þeir ríða til Lauga. Ósvífur fagnar þeim vel
Steinþór. They were twelve together. They ride to Laugar. Ósvífr greets them well

og synir hans. Bolli kvaddi Ósvífur til máls við sig og hefur upp bónorð sitt
and his (Ósvífr’s) sons (do to). Bolli summoned (kveðja) Ósvífr (Ósvífr is also the accusative form, ie the “r” is part of the noun stem; to demonstrate this also note genitive form, Ósvifrs later on) to conversation with him and raises (hefja) up his request (ie makes his marriage-proposal)

og bað Guðrúnar dóttur hans.
and requested his daughter Guðrún (in marriage).

En Ósvífur svarar á þá leið: "Svo er sem þú veist Bolli að Guðrún er ekkja
But Ósvífr answers in this wise: “So (it) is as you know, Bolli, that Guðrún is a widow

og á hún sjálf svör fyrir sér. En fýsa mun eg þessa."
and she herself has-the-right of answers (neut plural) (ie to answer) for herself. But I will urge this (ie promote your case).”

Gengur nú Ósvífur til fundar við Guðrúnu og segir henni að þar er kominn Bolli Þorleiksson
Ósvífr now walks to a meeting with (ie to see) Guðrún and says to her that Bolli Þorleikr’s-son is (has) come there.

"og biður þín. Áttu nú svör þessa máls. Mun eg hér um
“and asks for you (in marriage). You have-a right of answers (neut plural) (ie to answer) regarding this matter. I will, as regards this (see hér um, under hér, Z3),

skjótt birta minn vilja að Bolla mun eigi frá hnekkt ef eg skal ráða."
speedily reveal my wish (masc acc sg)  that Bolli will not (be) repulsed if I shall have-my-way (ie if the decision was mine).”

Guðrún svarar: "Skjótlitið gerir þú þetta mál og ræddi Bolli eitt sinn þetta mál
Guðrún answers: “You make this matter quickly-considered (pp as adj agreeing with þetta mál, ie neut acc sg) (ie you are rushing to judgement) and Bolli (nominative) discussed this matter one time

fyrir mér og veik eg heldur af og það sama er mér enn í hug."
with me and I declined rather (ie while not an absolute refusal it was still a pretty firm no) and that same (answer) is for me still in mind.” (The lady’s not for turning)

Þá segir Ósvífur: "Þá munu margir menn mæla að þetta sé meir af ofsa mælt en
Then Ósvifr says: “Then many persons will speak that this is spoken more from (out-of) tyranny (ie the arbitrary and arrogant exercise of your will) than

mikilli fyrirhyggju ef þú neitar slíkum manni sem Bolli er. En meðan eg er uppi
(from) great forethought if you refuse (say no to) such a man as Bolli is. But while I am alive (upright or above-ground)

þá skal eg hafa forsjá fyrir yður börnum mínum um þá hluti er eg kann
then I shall use (hafa, Z4) (my) foresight (noun) for you (ie I shall guide you) my children concerning those things (fem plural) which I am-able

gerr að sjá en þér."
more-fully (comparative) to see than you.”

Og er Ósvífur tók þetta mál svo þvert þá fyrirtók Guðrún eigi fyrir sína hönd
And when (ie since) Ósvífr took this matter (stance) so obstinately (Þverr, Z3 neut adj as adverb)) (ie dug his heels in), then Guðrún refused not for her part

og var þó hin tregasta í öllu. Synir Ósvífurs fýsa þessa mjög, þykir
and (but) was nevertheless (the) most-reluctant in everything. Ósvífr’s sons urge this much, (it) seems (present tense)

sér mikil slægja til mægða við Bolla. Og hvort sem að þessum málum var setið
to them a great gain (benefit) in an affinity-by-marriage with Bolli. And whether in these matters (it) was settled

lengur eða skemur þá réðst það af að þar fóru festar fram og kveðið á
longer or shorter (sooner or later), then that turned-out from (it) that pledges (fem pl noun) followed (lit: went forward, fara fram) there and (it) (was) fixed (determined, kveða á) on

brullaupsstefnu um veturnáttaskeið. Síðan ríður Bolli heim í Hjarðarholt og
wedding-meeting during (the) season-when-winter-sets-in. After-that Bolli rides home to Hjarðarholt and

segir Ólafi þessa ráðastofnun. Hann lætur sér fátt um finnast.
says to Ólafr this arrangement. He causes himself coldly (fár, Z2) to be pleased about (it) (ie he´s none too pleased).

Er Bolli heima þar til er hann skal boðið sækja. Bolli bauð Ólafi frænda sínum en
Bolli is (stays) at home until he shall seek (come to) the-wedding-feast. Bolli invited Ólafr his kinsman but

Ólafur var þess ekki fljótur og fór þó að bæn Bolla. Veisla var virðuleg að
Ólafr was of that not keen (ready, CV) and (but) nevertheless paid heed to (ie accepted agreed to, lit: went at, fara at) Bolli´s request (boen). The feast was splendid at

Laugum. Bolli var þar eftir um veturinn. Ekki var margt í samförum þeirra
Laugar. Bolli was (stayed) there after (that) during the-winter. (It) was not communicative (margr, Z3) in their travelling-together (ie through their married-life)

Bolla af Guðrúnar hendi.
Bolli´s (and Guðrún´s), on Guðrún’s behalf (part, side) (presumably lit: from the hand (perspective?) of Guðrún, see af hendi e-s under hönd, Z1) (This is MM&HP´s translation but I´ll also throw in an alternate reading: “lit: from the hand of Guðrún, ie on account of (af, Z9) (the) hand (ie behaviour, actions) of Guðrún” (ie Guðrún made sure there was little love in their marriage).