I suggest that you would need much more than 1GB of RAM to handle 'highest possible quality' renders. I have a Core Duo iMac with 2GB, and I have to reduce some settings to get reasonable render times - but with only minimal reduction of final image quality.

In your render settings, do you just move the 'auto' slider all the way to the right? If so, I would expect any reasonable size render to take a very long time. If you have a few figures with lots of polygons in your scene, and high-res textures, then 'a very long time' will effectively turn into forever, because you'll always end up cancelling it after a couple of days!

Have you tried a good-size render (say 4000px) on the 'Final' setting, rather than maximum?

(edit) - sorry, I'm assuming Poser 7 or Poser Pro - I'm not familiar with render settings in earlier versions.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)