Hi,
There are quite a few Family Karaoto releases. Is it the one with Metal Slug, Mario Kart? There are others that contains just standard Nintendo licensed games.
Dumping built-in games is difficult. Unless the games are present on a separate memory that can be desoldered then read with a EPROM programmer, you might want to send it to a professionnal (krzysiobal on nesdev.com forums can do that, for example).