Drive Problems

when turning a system on this morning it 1)
did not boot; i.e., blinking folder with the mac
face/question mark; 2) did not respond to a
straight hard reboot; 3) did not respond to a
restart & rebuild; 4) did not respond to
unplugging it; 5) while it brought up the
Software install disk (with a restart & C key), it
would not allow me to reinstall the OS.
Any Help would be appreciated!