I use only plain AutoCAD 2006. I think I have read something about animation capabilityes of 2007 but I can't offer any advice on that direction.
I created some animation in 2006 but just for fun. I wrote Lisp routines. In other cases I created screenshoots of the model and I assembled them in an animated gif file. See here a sample:http://www.cadtutor.net/forum/showthread.php?t=883
I think the best way would be to import the 3D models into a program like 3D Studio or so. Something created for rendering and animation. You could search something offering a free (say 30 days) trial period.