The safest cars nowadays are those with intelligent safety systems. The car I'm driving now is a good example. If I take my eye off the road and the car in front suddenly stops the car will brake for me. If I drift out of my lane the car steers me back.
When it comes to impact safety any car with a 5 star ANCAP rating is top notch. You can look up the ratings at
http://www.ancap.com.au