Always back up your data.

I came to my computer earlier today to find it on my Linux login screen. This could only mean one thing: something went horribly wrong.

Let me explain.

I have my BIOS set up to boot into Windows automatically. The exception is a reboot or something horrible happens and the computer crashes. Then, it boots me into Linux. Due to a hardware issue I never looked into, I have to be present to push F1 to allow the computer to start. The fact that it rebooted successfully, without me present, into *Linux*, could only mean one thing:

My primary hard drive died and was no longer bootable.

The warning was the BIOS telling me the drive was likely to fail ("Device Error" doesn't really tell me anything to be fair).

The massive wave of panic hit me.

I rebooted in hopes of reviving the drive. No dice.

I rebooted again. The drive appeared.

Let's see how much data I can recover from it before I can no longer mount it. Hopefully, I can come out of this relatively unscathed.

The drive in question is a 10 year old 1.5 TB Seagate drive that came with the computer. It served me well.

Press F to pay respects I guess.

On the bright side, I'll be getting an SSD as a replacement (probably a Samsung EVO).

!rant
Question...

I have a Windows 10 installation on my laptop...
A few weeks back my father bought an SSD for his Lenovo ThinkPad T500. Problem was - I couldn't install Windows on that laptop due to legacy BIOS (the T500 is old but gold). My solution was that I put the SSD into my eSATA portable HDD / SSD rack, and I installed Windows to the SSD on my laptop. It worked, but now, when I boot up my laptop it always asks which Windows do I want to boot up (only one Windows is present - the other throws an error). I switched the defaults, and now it boots up fine, but that choice really slows down my usually fast SSD boot (it has a 10 second timer before automatically chosing the default option).
How can I reconfigure it?
Or is it only possible by a clean install?

Another noob question.

After some searching I was only able to find the total opposite of what I wanted.

Is there a way to always automatically boot into BIOS instead of Windows without having to press any keys?

I've searched through the settings but couldn't find any.

Thanks