Timber the falling tree

Part I:
Recently some trees right outside our front door fell. The situation is this: we have some pretty tall and heavy (this is important later) hardwood trees around our house. They are nice to have in the hot summers because it keeps our house shaded. However, with any tree there is an element of danger, as in, oh-my-goodness-this-tree-may-fall-on-my-house danger, especially during a storm.