There are a number of posts asking what is good to start learning 3d and what free programs are good. Blender from blender3d.org is basically the top choice, or one of them, First it handles moddeling and animation well, all the normal features and a lot more. Then there is rendering, ray and buffer shadows, many material options, internal texture generation, or uvmapped textures, normal maps, specular and so on. Script support for most file exports and imports.

If you can't open it, it may be a version for another operating system, or your graphics system may not have opengl. (I think there is a workaround for that).