Hi all,
I'm currently using Zorin OS, but I'd like to perhaps explore other Linux distributions. Is it possible to dual-boot another distro, and then if I'm satisfied and after having installed all the apps I need, to erase my Zorin OS partition and only use the other, new distro?
You can install as many as will fit on the drive, there's no limit other than your own sanity
But will I be able to eventually remove OS #1 and switch to the one installed afterwards?
Yes, you just boot a live USB and use GParted to delete what you don't want anymore and grow the rest.
Based. Btrfs it is. Sounds like a really cool filesystem.
If you're using BTRFS and know how to/are prepared to learn, just create separate sub volumes instead of multiple partitions. Means that you don't need to decide how to split up space between different partitions and they are easy to delete without a live USB.