Quote - This sytem has 750MBs RAM, 1GB Virtual Memory, and..well, 1 GB left on the C: Drive.  I'm going to try to increase the Virtual memory to 5.25GBs(750MBs + 2GBs for Windows, 2GBs for Poser, and then if I want to open Photoshop...)

The 1 GB left on the C drive is the problem. Windows uses unused space on the C drive for the virtual memory, so you are probably running out. Try moving everything you can to another drive.  One of the problems with Windows is that no matter where you install software, there will be a footprint left on the C drive, so it will fill up even if you don't install to it.