What is the best Text type to use?

In a text object created with the text tool, I can choose "use system font" or "use bitmap font".  What is the difference between the two?  If I use bitmap font, then I have to choose between "embed" or "not embed"?  If I embed all the alpha and numeric glyphs, will that make may swf too big?   Of the combinations, which one is best to use if I am trying to get good readability on 10pt font-size?

how more characters you include in the swf the bigger the filesize (that can be a lot)

using bitmap fonts give you the freedom to use your "beauty" fonts, but you need to include the characters.

using system fonts it work the same way then with html, about the best "flash" font, I don't know but I remember there is information about on the net.