Connecting Ralf to a computer is probably less dangerous than putting anything floppy near him - disk or otherwise.
To do so, we'll need to find a computer that isn't being used.
Unlike normal walkthroughs, in Nice Game Hints you can select just the puzzle you want hints for. Here are listed the puzzles for "A Computer to Connect With" in Unusual Findings. The guide you choose only contains information about that puzzle, reducing possible spoilers for other puzzles.