Sorry guys, i expect this is a simple question for you more experienced players but still getting to grips with all the rules. When im commiting Thalin to a quest and the crows fly into the staging area , do they trigger the surge effect before they are automatically killed by Thalins damage or do they get killed straight away BEFORE the surge comes into play?

This one is in the FAQ. Thalin's ability resolves before any keyword or When Revealed effects. Good times!

Great, thanks for that. Tried to get into the FAQ bit all morning but it keeps saying its disabled. Cheers.

response is faster than when revealed and surge and doomed...

Thalin's ability is a passive, not a response.