Software Issue: Reinstall OS?

Okay here is my long and complicated story of my woes of the night...

I started up my Macbook and the Classic Apple showed up as per usual then a stop sign (circle with a line) showed up. I paniced and unplugged and took out the battery.

I did a hardware test and it said there was "no trouble found". So I am assuming it must be a software issue. Now I cannot boot up my Mac so I cannot check the disk utilities and such.

My question is: do I reinstall OS or do I go to a Genius Bar tomorrow to see if they can do anything?

I can only assume that I will lose everything on my computer if I reinstall the OS... But I will be upset if that is not my only option.

Has anyone seen or heard of this problem before?

If anyone is awake please leave a comment or message me. My life is on my computer and kind of freaking out lol.

Thanks so much!

1st try resetting the NVRAM/PRAM

If that doesn't work you may need to re-install. Using the Archive/Install option will keep all your data.

See this article.

Additionally, you can run Disk Utility from your System Discs. Simply boot up your system from System Disc 1. Then, you can access Disk Utility from the Tools menu. Make sure you do a Verify and Repair Disk as well as Verify and Repair Permissions.

When that's complete, you may also want to do a filesystem check (described in step 9 here):

http://www.mac-forums.com/forums/os-x-operating-system/93819-basic-os-x-mac-troubleshooting.html

It's almost never necessary to reinstall OS X.

thanks so much guys!!

I'll see how this goes!