Duff-Man says...the earth thing means it is trying to do a network-boot. Try holding the option key as you are start the computer and see if your local hard disc shows in the boot screen as a bootable device. If it does not, try putting in the cd/dvd that came with your computer (or a cd/dvd of the latest Mac OS that you have) and once it has booted from that (by holding the 'C' key at startup) you can run Disk Utility from there and maybe resolve the issue...oh yeah!