Windows 10 Upgrade Installation via DVD without booting into Windows 7

My Dad's laptop running Windows 7 crashed the other day, and after running Startup Repair, it found that compbatt.sys was corrupt. I tried copying over a good version from my pc & recovery partition but that only resulted in a blue screen.

Today, I attempted to do an upgrade installation of Windows 10 in order to preserve his files,etc.
We have a backup, but he's not 100% sure on it's content.

I was able to boot off of the Win 10 DVD and select Upgrade Installation, but then it stops, and a message pops up (paraphrasing here) that I need to boot into Windows 7 for it to proceed.

As I am unable to boot into Windows 7 due to the corrupt system file, I'm asking for a way to force Windows 10 to proceed with the Upgrade Installation WITHOUT having to boot into Windows 7.

I've prepared my Dad for the fact that we may need to do a clean install (7 or 10), and suggested we'd have to pull the HDD from his laptop and use my HDD cradle to scavenge for any files, but his laptop would take full disassembly (remove keyboard/etc) to get to the HDD.

Thanks for any help in allowing us to proceed with the Win 10 Upgrade Installation without having to boot into Win 7 which is corrupt. Googling hasn't given me any clue thus far.

Looking forward to people smarter than me helping me to a path forward without a loss of data and not having to take apart the laptop.

Unless you can repair the Win 7 installation, you're probably out of luck on the upgrade. Troubleshooting BSOD when you can't even boot to Windows is way beyond my pay grade. If you have no other alternative, a photo of the bluescreen would probably be a good start so others can know exactly what they're dealing with.

OTOH there are ways to retrive existing files without removing the drive: live Linux, Command Prompt in System Recovery Options, portable Win8...

Thanks for the responses. I'm currently using a rescue disk (KYHI from tenforums) and have coped files/used Macrium
Need to go over files with Dad and ensure we have what he needs before proceeding.
Based on response here, and other places, looks like my original thoughts will bear out. Clean install of 7 or 10, reinstall software, copy files from external drive/backup.

Thanks again for your time and input