Definitely Russia. Korea sounds like fun.
TAIWAN might be very interesting. There's a freaking 12,966-foot mountain in Taiwan:
Winter snow stays as late as April or May on the slopes of Taiwan's highest peak, Jade Mountain, which is also known as the "snowy mountain of the tropics." (Photo by Sie Sin-tian)
But # 1 on my bucket list - thanks to Spindrift and this thread - is I want to go heli-skiing and skin-skiing in Iceland. Not only does the country fascinate me, the scenery is spectacular and I can go salmon, char, and trout fishing while I'm there. Also, if you watch the movie "Prometheus", how could you NOT want to go visit Iceland?
# 2 on my list is to spend the last two weeks of March and the first two weeks of April in some small town in the Italian Alps. I know that the skiing may not be all that great, but everything else would be amazing.