As the "chime" is on then most probably the critical hardware is unharmed. Maybe it's the hard drive? But then you'd see a gray screen with quotation mark. Strange indeed. I'd try booting from a CD (while holding a C button on a keyboard), trying to evoke the boot menu (by holding Alt key on a keyboard) or resetting the PRAM:
1. Shut down your Mac.
2. Turn on the computer.
3. Press and hold the Command(⌘)-Option-P-R keys before the gray screen appears. (or Windows-Alt-P-R keys on a PC keyboard)
4. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
5. Release the keys.