It really depends on so many factors. In an appreciating market it would be better, but in a depreciating market you could be underwater in a matter of months. Ideally, 20% down puts you in a good equity position, allows you to avoid costly mortgage insurance and may provide a lower rate.
Sit down with someone you know and trust who is good with their finances and work through some options. Have enough in reserve for expenses such as repairs to the home or cars, being ill and other things you may not expect.