Macbook Grey White Not responding Boot Screen

Hello all,

my friend gave me her Mac to troubleshoot. I'm not sure what it's running on but can't seem to get past the white or grey backgrounds with the wheel. (They change)

I have tried literally EVERYTHING I can find on the internet.

- Resetting and doing the fchdsk

- Trying to start in safe mode (Does nothing)

- Using both V and user modes to start in safe mode (Does nothing)

- Plugging in a USB with the disc images of not one but TWO operating systems (The option does not recognize or respond to it)

- Trying to start in recovery mode

- Even went into the store, they said they weren't sure, (Go Apple)

I am thinking it's the operating system. She claims after one update it crashed and never came back on. The mac DID manage to load

- Twice but froze at a blue screen so I had to restart

- Once and let me register the mac and then froze at the blue screen

- ONCE FULLY OPERATIONAL but then it restarted to update then has not come back on.

I have an external with dmg files of both lion and Yosemite (I'm not sure which one is best for a macbook pro) I know the computer works. When I load in user boots or vibrose mode both say the "HD could not be modified" My external HD is plugged in, however when I press option it only gives me the option to chose the one hard drive. When I hold C the HD acts like it's responding and I know it is because it's flashing and sounding but the computer just won't load either of them. I don't have the disc and the repair utilities DOES NOT WORK (Command R does nothing) I know if there's just some way I can get back to the login I can reformat the HD and it'll load again. But I just can't seem to get the computer to move past the apple screens. I notice sometimes when I restart it's grey and sometimes it's white. The spinner is sill there but the progress bar disappears rather quickly without loading anything.

Without the disc utility I'm at a loss. The store said if the HD has turned on it works somehow. Is there any OTHER way to wipe it, get the computer to get past this screen. This is ridiculous. I've had a windows PC for almost 5 years, never once had this issue where I couldn't just reset the HD or get it past loading, (even in complete HD failure) but this MAC no matter what seem persistent on not wanting to boot up or taking quite literally HOURS to do so.