I don't think Europa has active geysers, but...
I recall a few suspicious images from Voyager 2 that were reported in
contemporary issues of Sky & Telescope magazine.
It would not surprise me if Europa did have them, though - just look at
Enceladus in the Saturn system.
Ganymede probably does have a liquid water ocean, but it probably is
buried under many miles of ice. However, perhaps by the time we can
send a robot submarine to Europa, we will be able to explore its neighbor's
ocean as well.
Callisto is probably all ice except at its core, but prove me wrong here.
Now for Saturn - I read that Dione is doing some "outgassing" as well.