In the case of tabletop games and computer games, some types of game simply translate pretty well, with some necessary modifications, across the two media. Strategy and tactical games are the example par excellence of this. Some of these games are even better at home on computers, because of what you can do in terms of graphics, animation, leaving combat resolution to the computer rather than the rolling of dice, etc.
Problems arise, I think, when attempts are made to hybridise these types of games with action games. Not that it’s impossible, but you can get some really strange results by mixing strategy / tactics game elements, who are always abstract at some level, with the more concrete, real-worldy / fantasy cartoon worldy aspects of action games.
A classic example would be the totally ridiculous numbers of levels and hitpoints in ‘action’ CRPG’s, where parties or even small armies (in MMO’s) just have to keep on whittling away at those hitpoints, rather than, say, use specific weapons and weak points:
‘Oh, look, it’s a dragon. Quick! Use a ballista with magically charged bolts to penetrate the soft hide on its belly’
versus
‘Let’s whittle away the hit points on its four legs’
