Recently, when I push the Standby button on the keyboard, the screen says that the computer is preparing for standby, and it acts like standby used to -- dark screen, lamp on front of computer case flashing slowly, and no fan sounds from computer case. However, when I move the mouse to "wake it up," I now get a blank cyan screen with an hourglass on it, then a black screen, followed by a standard boot sequence. This has been going on for 1-2 weeks. What can I do to get it back to the way it used to be?

Thanks.