Having done both emergency medicine and anesthesia, I would have to say that anesthesia is hands down a more pleasant specialty. Keep in mind that you may work less hours in emergency medicine, but the bulk of those hours will be evening or night hours, weekends, and holidays. If your husband works a 9-5 M-F job, this could really cause havoc with family life. The other downside of emergency medicine is the lack of specialisation, you are a generalist dealing with everything that comes through the door, and honestly, most of it is a glorified urgent care. You have to have extremely broad knowledge of every specialty, and all of that comes with high liability with regards to appropriate treatment. Oftentimes it is difficult to get consultants to come in and further evaluate patients.
Anesthesiologists may have call, but the typical work week is early in the morning to mid afternoon, and as someone stated call is interspersed amongst a large number of people. Most anesthesiologists have the day after call off, and go home early pre call. Oftentimes they even come in late on the day of call. There is no paperwork to do at the end of the day. All holidays are days off (unless you are on call) again dispersed amongst the whole group. It is otherwise a 6:30-7:00A to 12:00-4:00P job, M-F. Rarely do you ever need to answer your pager. Also, it is much easier to feel that you have substantial knowledge of your specialty.
My only regret in going back to residency to do anesthesia was that I did not pick it as my specialty the first time around.