A Professional Greeting. Your letter should be addressed to your boss. There's a good chance that this letter will merely end up in a file in HR, but it starts with your boss. Assuming this is someone with whom you work reasonably close with on a daily basis, it doesn't have to be super stiff and formal. Specific and professional is the right tone here.
Spot the Signs. The most obvious sign that you'll receive this reaction is if you haven't had a healthy relationship with your manager in the past. Maybe you continually challenged his ideas, and he took that as a sign of disrespect. Or, maybe she always made unreasonable demands, and you were never able to see eye_to_eye on your to_do list. Or perhaps his moods were completely unpredictable. In any case, if your relationship has been strained, you may receive a less_than_ideal response to your two weeks' notice.