If you put the eggs into cold water and then bring it to the boil, that will stop them cracking. Once the water's boiling, turn it down to a low simmer for about 5-10 minutes, depending how big the eggs are. As soon as they're done, put them straight into a bowl of very cold water to prevent the outer edge of the yolk turning grey.
EDIT: Making a hole in the egg will help stop it cracking, but you have to put it in the blunt end where the air sac is to stop the egg leaking out. This is quite awkward to do without either breaking the egg or stabbing yourself unless you have a specially-designed gizmo like my old Mum used to have!
Been boiling eggs for over 40 years!