I would say, this:
http://en.wikipedia.org/wiki/.NET_Framework[
^],
http://www.microsoft.com/net[
^].
The operation of stack vs. heap is quite obvious. If you need explanation, search for CodeProject answers. I answered similar questions good number of times and not giving you the references just because I understand that this is not your real question.
You should understand: you should not learn how to answer interview questions, you should get knowledge of technologies themselves. And you won't get this knowledge without practice and experience. However, from your question, I think you do understand it yourself.
—SA