If you want a free, easy to use animation program, the best program I can come up with is Pivot.
Pivot is a free stick-figure animator, basically it works on a frame by frame basis (unlike more advanced animation software that'll generate frames for you). It's a 2D animator (you can use your animation skills to make it appear 3D) and in general is used for very basic stick figure animating. The concept works that, you have a bunch of objects you can download or make, each object is made of LINES and CIRCLES. Every new line or circle in the object is connected by a pivot point (hence the name pivot), and you can move the pivot point to move the object in a certain way. Every object has a central pivot point that moves the entire object, it's incredibly simple and you can make some really awesome animations if you're willing to put in the time.
Here's a couple of example animations on youtube:
https://www.youtube.com/watch?v=H69SC-tFyNYhttps://www.youtube.com/watch?v=1PFJPg9BhSwAnd many more.
There's also a dedicated community for it here:
http://droidz.org/index.phpDownload is here:
http://pivotanimator.net/Although you can make some very good animations, it takes a VERY long time. When I did animations I'd run at 33 frames per second, so 1,000 frames (which would take days to make) would only be 30 seconds of animation