What skill would one use to “decipher runes”?
I would guess “Lore Master”, but the description of the skill is pretty specific. Is there a better skill, or does this sound right to you?
Scholar is the reading skill, right?
Scholar has “Reading: weird inscriptions”. You’d have to interpret “gaining information from one source in your language” as the result is in your language rather than the source. But I suspect in most cases you’d also need, in conjuction with Scholar, either the appropriate Language-wise, Wisdom of the Sages spell or equivalent magic item. Depends on what the root language of the runes are and if it was the same as the root language the reader knows.
While I realize that “runes” are an alphabet, in a fantastical context they aren’t just letters. Typically they have some “non-language” meaning, usually related to magic, that is akin to trying to garner meaning from a collection of Windings.
So, perhaps what I should have asked is, “what skill should you use do decipher a magical symbol?”
Lore Master is a slam dunk if these are magical runes, it is right there on the Recall Lore factors, “magical and arcane symbols” (p139).
What the…? How…? Well, in my defense, what’s the Obstacle to read game rules? 3-4? And I’m relying on Beginner’s Luck Scholar. 
What class are you? But Yes Dwight is wise as usual. I’d go with Lore master and (magical)Rune-wise.