Sorry for the vague title. I haven't used a Windows Laptop in about 4 years and the last time I reformatted a laptop around 2 years ago, I used Windows 7 (which turned out fine).
Recently, I had a friend approach me because her laptop died (Acer V5 - 471G, it was running Windows 8.1), she tried powering it up and it just gave her "Operating System Not Found". We backed up all the files that we can by opening the laptop and slapping the hard drive in a reader and copying the files I could still open. After placing the laptop back together, I tried installing Windows 7 (via DVD). At first, I had to figure out what was happening because my boot order wasn't being saved and I was going straight to the "Operating System Not Found" Error once more. I then figured out that the laptop was running a UEFI and not the Legacy type that's why the Win7 DVD installer wasn't being detected. I reverted it back to Legacy and then proceeded with the install. However, after installing Windows 7, the laptop was acting rather slow and BSOD-ed quickly. I think the laptop wasn't "Built" to run Win 7.
This lead me to think that I should install Windows 8.1 on the laptop. I acquired a copy of windows 8.1, but now, with all the new settings like UEFI and GPT, I am not sure how to proceed with installing at all. Does anyone have or can provide a fool-proof guide on how to do a fresh install of Windows 8.1? Any help for the uninitiated will be very much appreciated. Thank you.
Apologies if this isn't the network for this. I turned to superuser because I couldn't find a specific guide online.