I was ready to vote for good until the question was sullied by clarifying 'lawful' good. Sorry, if I had superpowers, chaotic good is the only way to go. I don't even understand how you -get- lawful good, given lawful characters invariably seem blinded by their I MUST ADHERE TO MY MORAL CODE and end up committing unthinkable atrocities. The law serves humanity, not the other way round.
So yeah. I'd be good, I'd help people, and I'd do it based on the harm principle, not the legal code of the country.