WE had one 2 years ago (but couldn't sell house, so are staying here, sob). It is pretty full on and expensive iirc. Chest X-Ray/ Various blood tests, Height/Weight/medical history from your GP. We all passed OK though.
Sorry, school run! When I went for my medical I was still carrying a lot of baby weight (and am not a slim jim at the best of times), if your BMI is high (and mine was) then you have to have an extra blood test. Mine came back fine. The high blood pressure may be a cause for concern. If she is really serious about emigrating then she could always look at losing some weight/getting fit, she'd have about 3/4mths notice anyway I would have thought. My Mom recently lost 3 stone and her asthma and arthritis have all but disappeared, it's amazing how weight can affect your health.