Power Which is the simplest way to add MySql and php functionality? Is there some tutorials? I heard that things are dangerous beacuse they can mess my Windows installation... Is that true?
AbyssUnderground PHP can be dangerous if you run a dangerous script. Commercial scripts should be fine but custom scripts by someone you don't know you should be wary of. www.abyssunderground.co.uk has tutorials for everything you should need.
rrinc Your best defense is to use popular projects (the code is well refined), your own code if you trust your own security knowledge, or other people's code that you can understand. In general though there isn't that much to worry about. Make sure you configure MySQL securely (good password, no remote access if it isn't necessary).