Thanks for your suggestions:
Problem solved!  I uninstalled Vista and reinstalled XP.  It was slowing down Carrara, Vue and anything else that used OpenGL.   Anybody want to buy a used copy of Vista?  (just kidding - I'm going to use the disc as a very expensive coaster)

Just FYI, I used "Dr Hardware", a hardware monitoring device, it benchmarks your machine and compares it to other similar systems.  With Vista, running my graphics was compared to a Pentium 2 machine.  When I put back XP, it was right back where it belonged, P4 with 2 gigs of RAM.   Did I mention I HATE WINDOWS VISTA!