I ate the shark meat and drank the brennevin when I was in Iceland. We were only offered small samples. When I travel, I try to eat whatever I'm offered.
The best thing I ate in Iceland was skyr, and I'm glad that it's available here in the US although I'd never noticed it before my trip. When I came home, I could only find it at Whole Foods markets, but now I can find it at supermarkets and even some smaller markets.