I have an old Subnotebook (at least 10 years old I think) which runs Windows 7 atm. I would like to run Linux on it. I‘m a Linux noob, but would like to try and learn a few things. Any recommendations?
Being lightweight or not doesn’t depend on the distro but the desktop manager (the graphic interface). Unlike Windows, the graphic in Linux is separated from the system so you can use different desktop managers on the same distros.
The lightest DE is LXQT but it’s pretty barebone, XFCE has more features while still being very light, avoid GNOME and KDE.
That being said, I suggest you try Linux MX XFCE or Mint XFCE first, if that’s not light enough for your liking, try Lubuntu, that’s Ubuntu with LXQT as default DE.
Mint XFCE or Lubuntu. I would try Mint Cinnamon first, to see if it runs properly. If not, try one of the above.
Mint XFCE
This is first stop, if this is slow than try something else.
My guess is it will be too slow, but it is worth a try.
Debian with LXQt. Good luck.
Debian XFCE