Macbook Start-up Trouble

Hello, I wanted to post here before I made an appointment with Genius Bar in case you guys had any solutions. I've had my macbook for a few months now and have had an excellent experience thus far. A few days ago when turning the notebook on the display stopped at the Mac OS loading screen (light gray background with centered dark gray Apple logo) and would not proceed loading to the desktop. On a few occasions, after waiting a bit the dark gray Apple logo was replaced by a gray folder icon with a question mark or a "(/)" icon (similar to the no smoking sign). I have attempted the trouble shooting techniques the Apple manual suggested which included shutting down while holding the "option" key then restarting and re-starting with the Mac OS software (upgraded to Leopard about a month ago) all to no avail. Now I believe the problem is that the notebook cannot locate the hard drive in which to start up on, however I have no idea why this happened suddenly or how I can go about fixing it. I'd like to preserve everything on the notebook already so I'd like to use the manual reset button on the bottom as a last resort. Please offer any advice you have!

 

Try resetting the NVRAM and PRAM. I had something similar happen to me a couple of days ago, and this worked.

Resetting PRAM and NVRAM
Shut down the computer.
Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in step 4.
Turn on the computer.
Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.
Hold the keys down until the computer restarts and you hear the startup sound for the second time.
Release the keys.

 

If you think it cant find the drive, have you tried checking the hard drive connection? Take the drive out and put it back in to make sure its in firmly.

 

Do the above, and if that fails, throw in your OS install CD, and boot off of that (Hold "C"). When it boots up, find Disk Utility in one of the menus (Can't remember which one off the top of my head), and see if your hard drive is even showing up.

If it does, run the disk first aid and try to repair it.

 

Its under the "utilities" menu. Don't know why tho... ;P

 

That's the one.

Oh, and if you do get it to boot up again, the first thing you should do is back up all important data, incase it happens again.