STuck at apple logo with some sort of loading bar that stucks half way. Can't repair disk with CMD R for some reason, any help?

Maybe this might help? Mac OS X: Gray screen appears during startup - Apple Support

1. Use your Time Machine Backups to restore your Mac.

2. Erase disk and re-install OS X.

3. If you want to attempt to rescue your data, get an empty USB External Hard Drive and install OS X on to that drive. Copy files (if possible) from corrupted Internal Hard Drive to the External Hard Drive and go back to #2.

Olsrud wrote:

PLS HELP, I HAVE SCHOOL ASSIGNMENTS AND ****, NOTHING WORKS, HELP ME MY MAC CAN'T BE BROKEN

You won't resolve your problem with frustration and shouting...

Olsrud wrote:

I sthere anyway i can time machine backup my files?

If you do not have a backup of your files then you have a few options that you can try but they will require additional devices and your patience...

If your Mac has the Thunderbolt port (or Firewire port), and you have an access to other Mac with Thunderbolt port (or Firewire port), then by using Thunderbolt cable you can get an access to your files on Mac with corrupted system. More info and requirements can be found in this document: OS X Mountain Lion: Transfer files between two computers using target disk mode

If you don't have an access to other Mac, but you do have an access to empty USB External Hard Drive, then by booting your Mac to Recovery Mode, you can install OS X on External Hard Drive (use external Hard Drive partition as a destination disk for OS X) and that will give you an option to access files on corrupted drive to copy them before erasing your Internal Drive and Installing OS X again.

OS X: About OS X Recovery - Apple Support

OS X Yosemite: Reinstall OS X - Apple Support

OS X Yosemite: Erase and reinstall OS X - Apple Support

How to install OS X Yosemite on your Mac - Apple Support

How to choose a startup disk on your Mac - Apple Support

"You cannot install Mac OS X on this volume..." alert in Installer - Apple Support

Hello I am having the same problem too. I run a computer lab at a high school and my macs randomly lock up during booting. I've unplugged and disconnected all cords. It works fine for a while then comes back. I ran disk utility and it seems to fix it once I can get it to boot in safe mode. I wish this problem could be solved for the long term but I am running out of patience. I have another problem and will post in another topic. Very frustrated with Yosemite.

Sincerely,

Mark