for married people - children
for singles - arts or entertainment circles
safe subjects with little chance of offending your group.
Religion and politics...... NO, just kidding, do avoid these at ALL costs!
Good subjects: Travelling i.e. experience of different countries - Childhood experience - "Anyone know a good joke?" often starts something... - Univers/ life elsewhere? - Energy - Global Warming.
Really depends on the company you're in so you should try chose the topic according the the people you want to converse with!
Talking about the weather,health and wealth .