Video Animation Software

Can anyone recommend me a Video Software which can be helpful to make 3D Video Animations like this one -
[YOUTUBE]http://www.youtube.com/watch?v=GfrAMveMsUI[/YOUTUBE]

I am crazy about combat planes and warships and I wish to step into this field, just as a hobby - not profession. But unfortunately I know nothing. I wish to acquire a software first, preferably a free full version. I can download from torrent if its available there, but I don't know the name of any such software or how to proceed.

Please help me.😃