If you want to make a game in flash you're going to have to learn Actionscript as well as animation techniques. I'd suggest you get to grips with Flash and how to make use of symbols and animation before getting stuck into Actionscript, which i'm trying to learn at the moment.

Here's a Flash site I made a few years ago.

http://www.riftwebdesign.co.uk/riftut/rift.htm

I used a book called "Teach Yourself Flash In 24 Hour's." By Sams publishing. Something like that will cover the animation aspects of Flash but the real hard work is learning the Actionscript which you need for complicated stuff like game's.