Thank you all for responding.  The first time I really noticed it, every single first render in either Poser 7 and/or Poser 8 hung.  I don't mind telling you I was really worried.  I kept closing and re-opening the programs (well I had to didn't I since they just froze) but the first render would hang.  So I decided to restart the computer, and that seemed to have had a positive effect, but it doesn't seem to be 100% reliable and I just wish I knew why it happened in the first place.

I thought about other programs running and causing conflicts.  I don't have Outlook, and usually only have Firefox and Thunderbird running at the same time...rarely Adobe Bridge and Photoshop CS3 too, but the most recent stalls were during sessions when the Adobe products were not active.  Just to satisfy my curiosity, I shut down Firefox and Thunderbird but the hang ups still persisted with Poser.

Luckily, the new computer reboots very quickly so restarting it is not quite the inconvenience that rebooting the previous computer was......is.