> [Ó-viturleg - in CV they give the Ú - negative - not Ó-neg - I think

it depends on your blood group]

This was a dialectal difference in Old Norse. Icelandic and some parts
of Norway had ó-, while other parts of Norway had ú-. But Icelandic
scribes were influenced especially in the later Middle Ages by
Norwegian spelling norms.

Perridon, Harry (2003). "Dialects and written language in Old Nordic
II: Old Danish and Old Swedish". p. 1018. Old Nordic III: The ecology
of language, in The Nordic Languages: An International Handbook of the
History of the North Germanic Languages. Volume 1. Eds. Oskar Bandle,
Kurt Braunmuller, Ernst Hakon Jahr, Allan Karker, Hans-Peter Naumann
and Ulf Teleman. Walter De Gruyter: 2003. ISBN 3110148765.

> hvert að þeir fóru
> where they were going

Exactly.

> Eftir það sáu þeir sól og máttu þá deila áttir, vinda nú segl og

sigla þetta dægur áður þeir sáu land

> [...] hoisting the sail [...]

'vinda' is the 3rd person present indicative, used here without any
conjunction before it. Lit. (with shifting tenses) "After that, they
saw the sun and were able to discern the directions, [and they] hoist
the sail, and sail [all] this day before they saw land".

> og ræddu um með sér
> and discussed (?) with themselves

Yes.

> skógi vaxið = viði vaxið

Lit. "(over)grown with woodland". 'skógi' and 'viði' are the datives
of the nouns 'skógr' and 'viðr' respectively.

> og létu skaut horfa á land
> and turned away from the ladn [I don't really get this]

Lit. "and made the corner of the sail point towards the land". Gordon:
"sail[ed] along the coast".

> Þeir spyrja hvort Bjarni ætlaði það enn Grænland.
> They ask if Bjarni expected it (yet) to be Greenland
> [were they getting seasick]

I'm imagining Bart and Lisa from the Simpsons chanting "are we nearly
there yet" ;-)

> Hann kvaðst eigi heldur ætla þetta Grænland en hið fyrra
> He declared for himself not to hold it to be Greenland more than the

former

"He said he didn't think this could be Greenland any more than the
land they saw earlier"
"He said he reckoned this [land] was no more [likely to be] Greenland
than the first/earlier/former [land they saw]"

> Þeir þóttust bæði þurfa við og vatn.
> They thought for themselves both wood and water were needed

"The believed themselves to both need wood and water"
"They felt that they needed both wood and water"

> vinda segl

"hoist the sail"