Headphones are definitely a good option. What's your budget like? If you're into home theater as you say then you may appreciate some hi-fi headphones like the Sennheiser HD800 or Beyerdynamic T1. Or more reasonably priced like the K/Q701, DT990, HD650, etc.
I am specifically recommending open back headphones because of their better soundstage and because they don't block out much outside noise. So if the baby is crying you'll still be able to hear them.