Actually I'm really wondering about the whole being able to see the BIOs and logos thing--as mentioned in the first post, pressing F5 or F12 gets me to an intermediate screen which then tells me to press F8 for advanced startup options. That 'advanced startup options' screen should be the exact same thing as the rest of the screens (plain white courier text on black background), and yet, I can never see it. It seems like there are just certain screens that either don't load or don't display.
Edit: So I tried your PE Rescue Disk again (replacing Boot.wim on a normal Windows 10 installation image) and after an hour of waiting for something to happen, it actually worked this time! I see the desktop shown in the thread. Am going to try it out right now, thanks for this!
Edit2: It seems that my GPU isn't being recognized. The only video device reads "Video Controller (VGA Compatible)" and its driver comes up as "Microsoft basic display adapter". I tried downloading the latest version of the Nvidia driver for my card and installing that, but it keeps failing--when installing it through "update drivers", it says that I don't have enough space, even though I mostly definitely do (8.16 GB in my C Drive). There are also two unknown devices, and I could not update the driver to the Nvidia one on either of them. I also can't get internet to work--no devices available apparently. There are some services that can't be found, like msconfig and the network troubleshooter. Is this normal or is my OS in general actually broken?