Well first of all wow your thinking of awfully high end
software for a beginner. For starting out I would recommend you check out some of the 3d forums on the net and try out some of the free software that's available sometimes you can get free older versions with Computer Arts or 3D world magazines.
Can't really compair your software choices: Maya is for building and animating 3d models and After effects is a Motion Graphics and Compositing tool for video.
I'm interested in learning how to create 3D animations (as a hobby - it has nothingh to do with my job). The best I could find, the standard software suitable is Autodesk Maya, and Adobe After Effects (perhaps alongside Adobe Illustrator). Which one should I chose, is there any other software that will do the job, and what are the differences between them?