BTW Cris, it may not help you, but also check your render settings.  Maybe you are just rendering at too high of a quality.  I used to try rendering at very high details and the program would always crash during the rendering process.  To find what works best though, you pretty much have do a bunch of playing around with the settings.  Eventually you will find your computer's maximum ability.

Just for your information too, the Temp folder is just where Poser stores calculation and rendering data that gets overwritten every time a new render is done.  Basically, Poser is constantly deleting files and writing new ones to that folder, so deleting it really doesnt do anything that Poser is already doing.
I just wanted to make sure you walked away knowing exactly what that folder was.