Hi Larry,
Yes, you can change the OS on your PXI-8176 controller. For directions on how to change the OS, please review "Restoring or Changing the Operating System in a PXI-8171 Series Embedded Controller" at http://zone.ni.com/devzone/conceptd.nsf/webmain/26F082D561C912BB86256D080074AD58?opendocument. That tutorial should be able to answer all of your questions.
Regards,
David Shatila
Applications Engineer
National Instruments