First read stuff by Tufte and Tognazzini and Cooper first.
Learn Flash second
Learn Flash second
http://en.wikipedia.org/wiki/Form_follows_function I live by this in interface design. First decide what funtion needs to happen, then decide on the best visual representation or form to achieve this. Basically this means the technology should not dictate what the interface or idea is. If you come up with a great idea, then you can explore what technology you need to execute it at the highest level, be it Flash, or another method.