[brendaningram]

Firstly, what I use and where I'm coming from: I've distro hopped in VirtualBox (so I can experiment) for more than 5 years, trying out every distro I can find. I currently run Debian with i3 natively / on the host machine. It certainly classifies as "lightweight", running in not much more than 100MB of RAM. It's blazingly fast on my 32GB i7 desktop or my 10 year old laptop.

Secondly, to answer your question "What Linux distro should I start with?" If you've used Debian before, and you know what i3 is, you aren't a Linux novice. So I would recommend staying with the Debian/i3 combination. It will run perfectly fine on the 6 year old laptop you mention.

I think the strongest piece of advice I could give you is "choose one distro/DE combination and stick to it - when the use of that environment becomes second nature you'll have more mental capacity to focus on and learn other things (like C)"

There was a mention of Fedora down below, and I have to give this a big thumbs up. Every time I use Fedora, I find it "just works". Problems with Mono/MonoDevelop on Ubuntu? Works perfectly on Fedora. Problems with GOPATH/PATH with Visual Studio Code on Debian? Works perfectly on Fedora. If it wasn't for the fact that I've spent the last 10 years becoming familiar with the Debian/Ubuntu way of doing things, I would swap to Fedora in a heartbeat. And to be honest, every time I look at the Fedora community, I just have this gut feeling that it's the right place to be.

P.S. I wrote up a bit of an article about something similar last year. If you're interested, you can find it at https://brendaningram.com/article/ram-usage-of-various-linux...