1. Unless you have a very peculiar hardware configuration or so, the installation is about as easy as they come. Run the installer. Answer the questions. Edit your xorg.conf to make sure glx is enabled and "nvidia" is the driver. Done. Of course, you may add more options if you want/need to (it's all there in the readme file).
2. fglrx? That's ATI and not NVIDIA.
3. The "no screens found" error...well, if you're using a sample config, I'm not surprised, since it most likely doesn't contain any data about your screen. Just modify a working xorg.conf.