Use of Же

[mangiami.livejournal.com]

How do you use же? Is it just placed after whatever you want to emphasize? Are there any times when it should be especially used, like after a positive command using an imperfective verb, such as in:
- Открой окно, пожалуйста.
(after waiting a minute)
Ну, открывай же!

(If this is already answered elsewhere, please refer me to it, and I apologize for this post in that case.)

(no subject)

[bolnaia-sobaka.livejournal.com]

How would you say:
- "to dare"
- "to be bold enough to" ?
Here's the sentence I am (unsuccessfully) trying to write:
I find it bold to ask more about you, since I was already bold enough to dare speak to you without an introduction.
Мне кажеться (отважно, смело ?) спросить больше о вас, потому что я уже посмела с вами говорить без представления.