Trisquel, followed by gNewSense/Musix. Dragora actually seems to be preety
intimidating difficulty-of-maintainance wise.
And the OS is GNU. Linux is a kernel. Operating systems need a kernel (and
the FSF don't seem to have home-grown ones that can compete against Linux),
but that doesn't mean it's named after the kernel it uses(take a look at
Android, for example. It uses Linux, but the OS is still Android - a
different one to GNU).
Let's put it this way: If you put a Wankel engine from an FD Mazda RX-7 into
a VW Combi, the Combi is still a Combi, isn't it?