Re: nvidia_drv.so - cannot open shared object file: No such file or directory
I'm not really sure what is happening on your system at this point, but it seems possible that your X server is broken if it can't load a driver which clearly exists. In your X log I see a few modules are also failing to be found (xie, speedo, etc). Do those exist on disk?
Is the Xorg that you're running the latest version for Debian?