That's right. Meg expresses contrast between the clauses, so, for instance, it would be correct to say "én nem cigarettázom, te meg igen". But since this is a question, the speaker doesn't know if there's a contrast or not, so meg can't be used.
"és" is the general word for "and", always use that if you're not sure. But sometimes you can also use "meg" instead of "és", for example if you're listing things:
"I buy bread and milk." = "Veszek kenyeret és tejet." = "Veszek kenyeret meg tejet."