MacbookPro won't boot/hard drive won't mount

This started a couple days ago.

I just finished streaming a show and tried to nav a page back when my computer went unresponsive. I got the spinning wheel cursor and waited a while for it to fix but it stayed unresponsive. So I shut down the computer using the power button. Upon attempting to power on again, the boot screen would show up and the progress bar would go about a fourth of the way before suddenly shutting down again. I tried a couple more times before I started to research on the Internet for some solutions. I tried opening up disk utility and noticed Mac HD was grayed out. i attempted to repair disk but after some error messages it said it could not be repaired. I tried booting in safe mode that same night but it would keep shutting down during boot. So the next day (yesterday) I tried again to boot in safe mode. This time it worked and I was able to see my desktop. I then tried to open Finder, but again The whole computer went unresponsive.

I do not have a backup of my hard drive so yesterday I went out and bought an external hard drive to try to backup my computer before trying anything else. But again, my HD will not mount while in boot up Disk Utility so I can't even try to make a backup. What I'm trying to do right now is boot into safe mode to try disk utility from there to see if my HD will be mounted.

I did notice a repeating sound coming from what I believe is the hard drive when my computer is unresponsive. The sound reminds me of a slow heartbeat with the faint pattern of a rotary phone spinning back to 0. I know that's kind of a strange description but this is hard to put into words.

I have a lot of family photos and music I would really like to not lose, so if anyone has any tricks up their sleeve for helping me create a backup in this situation, it would be very greatly appreciated. If you need more specific info such as Disk Utility's repair errors or whatever, let me know.

A couple side notes: I've seen mention of costly things such as Disk Warrior, but I don't have the funds to afford something like that.

We do not own another Mac so connecting two together is not an option.

I'm running a 15" Mid 2009 MacbookPro with the most recent version of OSX