HP TS 15-j040us OS/Software :: Can't Download Driver Needed To Upgrade To Windows 8.1

I have a Touchsmart 15-j040us notebook that is now a little over a year old (now out of warranty). My laptop has been asking to upgrade to Windows 8.1 since the first week or two after I purchased the system brand new.
 
The update downloads just fine and begins the install but fails every time when it is trying to install the different devices. At that point the screen goes black, the laptop reboots and I get an error message saying that update did not work and that the system has been restored to its previous condition.
 
After working through HP tech support, including sending the laptop to them to reimage, I am still unable to perform the update, which means my laptop is incapable of running the apps and programs that HP says my laptop is ready to run.
 
I am fairly confident that the issue is the Nvidia video driver. The currently supported version (version 9.xxx) of the driver is not compatible with 8.1. HP has a driver listed that is compatible with 8.1 (version 10.xxx), but I can't download it until my laptop is running 8.1. Nvidia has posted on the site a driver that is compatible with both operating systems, but I can't seem to download and install it so that I can perform the update. How to download the driver from Nvidia so that I can perform this update?