There are many great benefits of yoga, such as increased flexibility, improved relaxation, and core strengthening. I especially recommend it if you do no other form of stretching in your daily routine or workouts. Even doing yoga 1-2x/week is beneficial for your overall health and will contribute to your less painful future. If you do not belong to a gym, a yoga DVD is a convenient option. Yoga is a great choice of exercise during pregnancy.
Having said that, I personally do not take time for yoga. I have two children and I work part-time, so realistically I exercise 3-5x/week. When I go to the gym, it is only for an hour, so I fit in 30-40 minutes of cardio (usually in intervals), 15-20 minutes of strengthening, and a few minutes of stretching.
Yoga is not for everyone. Most men do not like it. Also, some of the positions cannot be tolerated if you have back or joint problems. Some yoga positions could even exacerbate an injury or a chronic orthopedic or spine problem. So be sure to listen to your body; you can always skip or modify some of the positions/stretches.
Finally, as far as meditation goes, I personally prefer to meditate by reading the Bible and praying, and I highly recommend it!