I got up this morning to turn on my MacBook Pro, and it was unresponsive, stuck at the gray screen with the spinning circle. There's also a loading bar beneath the circle that disappears after a few seconds. I already had a similar encounter about a year ago with the same computer, and took it into the Apple store where they eventually had to replace the hard drive.
It's a 15" MacBook Pro that I got about 3 years ago, currently running OS 10.6. I don't have the OS disc with me but I do have a time machine backup on an external drive, but I'm having trouble figuring out how to boot from that. I also have access to my girlfriend's MacBook Pro, which I'm posting from. It's newer and came with 10.7 installed, which it is currently running. I read online about being able to create a 10.7 boot disk by re-downloading the installer from the purchases section of the app store. I was going to try this, but since this MBP came with 10.7 already installed and was never purchased, I can;t find any way to access the 10.7 installer since they have removed 10.7 from the app store entirely it appears. I would just go ahead and download 10.8 for the $20 on here and create a disk from that if I knew there was a good chance it could fix my problems.
I'm no expert, but following what others have posted about similar problems, I booted using CMD + Shift + V, and the last few lines contain things such as:
Keys out of order (4,7898)
Rebuilding catalog B-tree
The volume Macintosh HD could not be repaired
This is where I get lost and don't know what, if anything, can be done from here. I was just hoping there was maybe something else I could try before taking it into the Apple store, as the nearest one is about 100 miles away. Any help is greatly appreciated.