Definitely some difficult language in this passage:

"Dróttinn argrar dróttar einnar, Veiði-Anakinn," segir Víga-Óbívan.
"A cowardly lord of only people, Vader Anakin," says Slayer Obiwan.

Síðan hljóp hann fram með brugðit sverð ok hjó þegar til Veiðrar en hann hopaði undan.
Then he leaped forward with drawn sword and struck at once at Vader but he drew back.

"Þú ert orðinn veikr, gamall maðr," mælti Veiðr.
"You have become weak, old man," said Vader.

"Enn færðu eigi haft mál þitt, Veiði-Anakinn," segir Víga-Óbívan, "Ef þú slær mik niðr, svá monk verða sterkari an þú fengir trúat."
"Still you are not able to win your suit, Vader Anakin," says Slayer Obiwan, "If you put an end to me, so I will become stronger then you are able to believe."

Veiðr hljóp út þegar ok hafði brugðit sverðit Ljósamæki inn rauða.
Vader jumped out at once and had drawn the sword Light-saber the red.

Lengi bǫrðusk þeir, ok vǭru þeir jafndrengilegir, ok engi gaf upp.
They long fought each other, and they were equally-brave, and no one gave up.

Nú beint summu þau Hólmgǫngu-Hani aptr til Dauðastjǫrnu, en hermennirnir geymdu þau eigi,  því at þeir athuguðu hólmgǫnguna Veiðrs ok Víga-Óbívans.
Just now they, Dueler Han (and the others) swam back to the Death Star, but the warriors didn't heed them, because they paid attention to the duel of Vader and Slayer Obiwan.

Ok es Leia konungsdóttir sá skipit Falkann, sagði hon Hana, "Þú stýrir þessu skipi?
And when Princess Leia saw the ship Falcon, she said to Han, "You captain this ship?

Svá ertu djarfari an ek hafða trúat."
So you are more bod than I had believed."

En Lúkr spurði Hana, "Es skipit í lagi?"
But Luke asked Han, "Is the ship in order?"

"Svá sýnist þat," segir Hani, "Ef vér fengum þagat komit.
"So that would seem," says Han, "If we are able to come there.

Þess vonak, at inn gamli maðr gefi Veiðri hart slag, til þess at vér fengim komizt undan."
I hope that, that the old man gives Vader a hardy blow, so that we are able to escape." (Z. has "slag 2 - gefa e-m s., to defeat," but I don't think this applies unless "hart" can be an adverb, which I don't see in Zoega)

"Þá fǫrum vér sem bráðast," segir Lúkr, ok hljópu þau ǫll til Falkans meðan hermennirnir geymdu hólmgǫnguna.
"Then we go as quickly as possible," says Luke, and they all jumped aboard (the) Falcon while the warriors watched the duel.

En Víga-Óbívan sá hlaupit þetta, ok þá íhugaði hann þat, at hann fengi eigi unnit Veiðr yfirkominn, en hann vissi þann galdr, es hann fengi sunginn, til þess at maðr fengi lifat eptir þat at ættmaðr sinn hefði hann drepinn.
But Slayer Obiwan saw this leap, and then he considered that, thathe was not able to succeed in vanquishing Vader, but he knew the magic song, which he was able to sing, so that a man was able to live after that, that his kinsman had killed him. (Z. has "vinna 12 - fá ekki at unnit, to effect nothing," but I don't think this applies here)

En þat fall hlýtr valdit af þeim manni, es hafði kyn sitt eigin svikit, ok maðr svá drepinn fær lifat ósénn ok ósnortinn svá lengi sem hann hvetti ættmenn sína til þess at drepa svikarann.
But that fall is obliged to cause of the man, who has his own kinsman betrayed, and a man so slain would be able to live (ósénn? not at the same time??) and untouched so long as he would encourage his kinsmen to that, to slay the betrayer (?).

Ok maðr sá, es sǫng þenna galdr, þó ósénn ok ósnortinn af ǫllum, væri heyrðr af mǫnnum þeim, es sóttu at hefna hans.
And a man saw, this song is a magic song, yet (ósénn) and untouched of all, were able to hear of the men, who sought to avenge him.

Slíkr galdr fengi òk hætt við ǫll galdralǫg, þau es svikarinn sjálfr hafði sungin, ok þess vegna fengu þeir Lúkr komizt undan ok lifat til þess at hefna síðarr.
Such a magic song would also (òk = ok?) be able to risk with all magic-laws, that which the traitor himself had sung, and that on account of they, Luke (and the others) would be able to escape and live in order to revenge later.