1. AIR applications use Adobe Acrobat or Adobe Reader to display PDF content.
3. PDF is the best solution for printing rich text in AIR. But you can also print text from SWF content. (For example, you could use the Flash Text Engine features made available in AIR 1.5.)
For details on using content PDF in AIR, see this:
That is not an easy thing to do. Even if I do that, will I have silent printing?
But first of all, how to add JS to a dynamically created PDF?