You suggested Kubuntu which is KDE. which will be way to slow for them. I never suggested Gnome… 🧐

Xfce or lxde would be way better, like others have suggested.

They want a desktop, not a slideshow.

I dont know if this is the issue, but is your motherboard bios up to date? I had some weird error like this before and after updating my bios it worked.

C: “Segmentation fault.”

Where?

C: 🤷🏻