What OS is this?
What OS is this?
appears to be an earlier version of Knoppix, yet it seems similar to other KDE-based distributions.
Wherever you are, it relies on SUSE with workstation boots from a central server.
Seems like a variant of Eastern European Linux, possibly resembling Kaspersky Disk.
The desktop setup is definitely KDE. It confirms this right from the initial screenshot, and I believe the Linux desktop interface effectively conceals what's happening beneath the surface, making it hard to identify the specific application just by looking at the menus.
I think it's an older KDE release or one of those lightweight distros that run in a few megabytes, offering only the essentials for very old machines or for quickly creating bootable USB drives to fix them.