"1. Iceland has glaciers. It is not hard to find photos of Iceland showing snow on the ground, apparently somewhat stable. How do these facts relate to the hypothesis of 200W/m2 heat flow?"

Would you agree that over active volcanic areas you can have some condition where there is more than 200 W/m2?

You would agree that over region the size of the Antarctic [larger than the US] there are some active volcanic regions?

Perhaps you seen some news regarding active volcanic region in western Antarctic.
Here is one:
"Another factor might be contributing to the thinning of some of the Antarctica's glaciers: volcanoes.

In an article published Sunday on the Web site of the journal Nature Geoscience, Hugh Corr and David Vaughan of the British Antarctic Survey report the identification of a layer of volcanic ash and glass shards frozen within an ice sheet in western Antarctica.

"This is the first time we have seen a volcano beneath the ice sheet punch a hole through the ice sheet" in Antarctica, Vaughan said."
http://www.iht.com/articles/2008/01/20/europe/climate.php

Perhaps also in the news, in the relatively recent past you noticed stories of large ice/water flows in Iceland caused by volcanic eruptions?

Perhaps you aware that in volcanic regions the ground can become warmer before or long after an actual eruption event.

Or for instance if an area has hot springs, then it probably a volcanic region.

"2. A queen-size electric blanket apparently draws about 200W when heating. So about 50W/m^2. Think about how warm an electric blanket gets if you have it set to "MAX". Think about how much warmer it would be if you piled four such blankets on top of each other. Do you think it is likely the ground over the entire island of Iceland is that warm. Refer to thought experiment #1 if needed."

Well first, a human body generates about the same heat as your electric blanket.

But I'll tell you what, you can go outside in the snow while it's snowing with your electric blanket turned on to "MAX", plus you get one large raincoat. And for additional blankets, you get a shovel so you can pile snow on top of you.