If they like Clue (the board game) they might like Guilty Party. We played it over the last week, (DD8, DH & I) and we had a hoot. Mario Party and Wii Party are also board games type games, but are lots of fun too.
If they're looking for an low impact exercise game, maybe Walk it Out? I've found it highly addictive and it's got lots of positive reviews from all age groups.