Upgraded to Windows 10 & All Hell Broke Loose! Rendered Hopeless. Help

So the task bar told me to upgrade, so I did. Windows 10 seemed to run very smoothly, until I noticed I had no sound output. So I opened device manager to find my soundcard unrecognized. I visited ASUS' site for appropriate windows 10 drivers, updated & rebooted. I obtained a BSOD loop saying CRITICAL_PROCESS_DIED. I've tried everything, startup diagnosis & repair, safe mode does not work etc. I attempt to repair the boot sector by selecting command prompt and typing bootrec /fixmbr, bootrec /fixboot & bootrec.exe /RebuildBcd. Not knowing which to select afterward, I selected ALL, which may have been a fatal mistake because now, when I boot into Windows 7 I get a shitload of errors like Windows LogonUI.exe> The program can't start because api-ms-win-core-libraryloader-l1-2-0.dll is missing. Slui.exe> Entry Point not Found. And a whole bynhc of other errors about .exe's it can't find. So now I'm just wanting to back up what I can and start over, but I can't. pretty much everything is FU$&%D. I can run firefox to post this, but nothing else works. IE Explorer, Windows Explorer, Control Panel. Nothing essential works. I can't wipe this computer until I pull some of the data off of my primary C:. I downloaded a 3rd party file manager which I can see everything but I cannot click and drag, copy and paste does not work. It also no longer recognizes my external disk drive. I've used the sfc /scannow command and it said some files could not be recovered, it seemingly did nothing to help. One more thing, after this disaster took place I now have a 'This copy of Windows is not genuine' in the bottom right corner of my screen. I've also tried system restore but it says there are no restore points. There must be a way to crutch through this so I can recover my data before wiping. Can someone please help me with this?! I'll be so grateful. I spent hours on the phone with microsoft and they are completely useless. Thanks

P.S. I tried downloading and installing the log collector but i get an error saying Ordinal Not Found. The ordinal 854 could not be locatedin the dynamic link library ierutil.dll

And another error saying dxdiag.exe - Entry Point not Found. D3DKMTNetDispQueryMiracastDisplayDeviceSupport could not be located in the dynamic link library GDI32.dll

I clicked through the errors and it seems to be doing the scan. Stay posted. Thanks.

Okay so the saved log file is in a zipped folder on my desktop but I cannot access it. I cannot double click it or right click it, it's dead. I can double click and right click other files on my desktop however.

So I have uploaded the zip file as I cannot open it or save it at all from my desktop. This PC is so messed up that 90% of things don't seem to work. Please help!

Okay I wasn't sure which one to use since I'm kind of stuck in between both version of windows, both not working. I would happily ditch Windows 7 if I could get Windows 10 passed the blue screen, which I don't think I'll be receiving help for on sevenforums. Thanks

Maybe someone has thoughts on possible fixes for the new installation of windows 10?

Boot into safemode in the Windows 10 and uninstall the new sound card driver. See if you can boot into Windows 10 normally then, even without sound. Then go to the manufacturer of the sound card (or chip) and install their driver - probably Realtek.

Worst case: backup your hard disk to another computer, then wipe and reinstall Windows 10. If the other computer is a desktop model, then you can connect the SATA disk directly on the motherboard as a second disk. Copy all the necessary folders from D:\USERS\username where D is the letter your disk becomes in the other computer, change as appropriate. Then download the ISO from here. If you have 4GB or more RAM you need the 64-bit version, otherwise the 32-bit version is recommended. All ISO contain both the Home and Pro version. When clean install skip entering a key, but make sure you select Home or Pro depending on your previous Windows version, or you won't be able to activate. After successful installation of Windows 10, visit your manufacturer's site and have a look at the drivers. I recommend downloading every Intel driver directly from Intel's website and any other (eg Realtek) directly from the respective OEM. The rest drivers which you cannot find the OEM site, you can safely download them from notebook's manufacturer site. Avoid any useless utility, download only drivers.