Around '99 or '00. A friend of mine was gifted a Linux Magazine subscription and made me a copy of the CD. It was noteworthy at the time because it didn’t have any copy protection and we were neck deep in piracy, keeping our friend group supplied with copies of games that we pulled off of IRC.
Getting a CD full of software that made no effort to prevent copying was intriguing enough that we sacrificed a spare machine one weekend (giving up the ability to play LAN StarCraft!) to see what another operating system looked like.
We tinkered on and off for a year, once we could get dual boot working (thanks to the IRC crowd) we used it a bit more often. Mostly ricing, though that wasn’t a term at the time, and playing with the hacking tools (for educational purposes only, of course).
I think there was some copy protection mode that was annoying to write on Windows but trivially easy on Linux, which was the first time that I can remember where it was just better than Windows. That, and ARP poisoning our LAN parties to packet capture and read people’s AIM and ICQ conversations because we were little shits.
https://en.wikipedia.org/wiki/Linux-libre
It’s essentially a kernel with only open source code. OP would need to research all of the hardware in their machine to ensure that there are open source drivers. I think there are some laptop manufacturers that sell units which are compatible, if you’re ordering from one of the major manufacturers then you’ll likely have some hardware (like wifi) that requires proprietary binaries.
The hardest part is usually finding a machine that has open source drivers for every component. You may have to do some kernel compiling and other low level tasks to get your specific setup to work. OP says they’re not a power user, but after this they will be