Hi AFCB,
I think your windows is more stable as if you only 4 system crashes between 14 to 19. Three windows crashes are related to bdfsdrv.sys and it is BitDefender Internet Security software. You install this software recently. If you keep on installing new software, you have to make sure that they are stable. The CPU_CALL_ERROR is still unresolved . Probably the problem maybe related to motherboard as the crash instruction is consistent. Upgrade the BIOS of your motherboard. If your windows is still crashed with CPU_CALL_ERROR, replace the motherboard.
Debug report
Mini121406-01.dmp BugCheck 44, {855f5648, d62, 0, 0}
Probably caused by : bdfsdrv.sys ( bdfsdrv+ff2 )
Mini121606-01.dmp BugCheck 10000050, {e3f0b000, 1, ac993ddb, 1}
Probably caused by : kmixer.sys ( kmixer!Convert16+db )
Mini121906-01.dmp BugCheck 44, {863e9e28, d62, 0, 0}
Probably caused by : bdfsdrv.sys ( bdfsdrv+ff2 )
Mini121906-02.dmp BugCheck FC, {b97a57d8, 1d564963, b97a572c, 1}
Probably caused by : hardware (probably it is related to faulty m/b or bdfsdrv.sys)
Edit: Your nVidia Display Card Driver may have software problem as I have several opened cases relating to this version of nVidia Display Card Driver. Their symptom looks like memory corruption. If your windows does not crash at safe mode, probably video card driver is the culprit as safe mode uses MS graphical driver.