I could be wrong, it's happened before, however is your drive defraged so that it is a contiguous free space?

I've had these happen on my machine with 384 Mb ram. I tried moving poser to my temp file HD with 9 Gb or space and bang no problems no matter how I loaded up the scenes- I think what is happening is Poser grab a monster chunk of HD space for a temp file when it renders then lets it go, run of of HD space and crash. Hope this helps. btw I couldn't find any preference setting for temp files, like Premiere has and others.

If you can find it this book is great on aesthetics and theory: Herbert Zettles "Sight, Sound, and Motion" also Lenny Lipton has some interesting books, titles escape me. The Malkeiwicz book above is one the the best survey books.