You may have noticed that in professional flash websites they use very fine and clear fonts. What most people do, they just take text tool in flash and write a static text which will probably not be so clear in looks. Follow this rule to use clear style fonts in flash.
I suggest you something.
Never take static text :)
Instead take Dynamic text.
Tahoma 10 for normal text.
Click <> sign for render text as html.
See the result and that will be very exact clear text as than before.