After rolling back to that driver and and installing the fresh beta version of New Vegas Anti Crash my game worked just fine again.
After some research google confirmed that it was indeed the new Windows 10 Update that made Fallout NV (and apparently even Fallout 3) unplayable, if you have an Nvidia Card with a driver newer than version 368.81. Select Troubleshoot Compatibility and choose Troubleshoot Program Check the box that says The Program requires additional permissions. Right-click on the Fallout: New Vegas launcher application found here: C: Program Files (x86) Steam steamapps common Fallout New Vegas (by default) or C: Steam Library steamapps common Fallout New Vegas.