Straying off the beaten track, for newcomers to anything, is not recommended. In time one can do it - no doubt about that - too soon is diving in the deep end.
Yes, there can be many, many ways to achieve the same thing. I suggest you try the Ubuntu way, ie Ubuntu nvidia packages. The nvidia installer has this option you should run first,
Uninstall the currently installed NVIDIA driver.
Install the .debs (which should handle necessary kernel modules) and edit xorg.conf,
- remove the loading of dri module
- keep the glx module
(I'm not sure how Intel graphics handles the above)
- the "Screen" section references a "Device" section by a name you give, it can be "Intel Corporation 82915G/GV/910GL Express Chipset Family Graphics Controller" or "mycard" - up to you - the names you give have to be the same in both places
- your main "Device" section needs to have a 'Driver "nvidia"' (multiple device sections are possible but you will only use 1 at a time)
- reboot to enable the nvidia card in bios