Sorry about the title, I just had to do it ;)
I've found that if you want a really easy and quick way to gain a general idea and understanding of such concepts as layering, animation and timelines, and graphic design (such as masking, transformations, filtering, etc) that you take a look at FLASH and Adobe (any Photoshop x.x or CS2 are fine). Both come with easy to follow lessons that walk you through some of these concepts. Learning the concepts through these 2 technologies allows you to visually perceive what is actually going on. You will learn what such terms as 'masking' and 'skewing' mean and actually see what they're suppose to do.
I've found this to be a very fun way of getting started. Maybe you will to, especially when an integral part of any final game is its graphics and animation.
Another bonus is that once you're done with these lessons, and you've played around with your new learned skills, you'll be able to create amazing art work, banners, and even logos for your websites.
