Poser crashing while doing movies is not that uncommon. I find rendering as a series of stills works most reliably. As a quick check of motion I use the preview render setting and an old avi codec.

 

I run poser 7 on an athlon 2.08 ghz processor with 512 mb memory and 10-20 gb of available disk space.  Not the best but workable.

For 64 bit processors load up on memory 4gb - 16 gb depending what else you run .

Poser doesnt need a very good graphics card yet.