MacBook Pro Not Partitioning Hard Drive

Hi All,

I recently downloaded Ubuntu from their website on the recommendation of a friend to try it out.

My issue: I'm trying to partition my hard drive but it is stuck on a blue loading bar of "Preparing to partition disk". It has been stuck like this for ages (I left it overnight).

It might also be related to problems I had when dual booting my MacBook Pro with Windows 8 (I was forced to erase that partition and start over). By the way, my disk is partitioned as Macintosh HD (OS X 10.9), diskOs4 (no idea what this is but it came with windows 8.1 and BOOTCAMP (Windows 8.1 Professional or something)

Is there another way to partition your hard drive with out losing its contents or a fix for the disk utility issue.

My specs are:

MacBook Pro (13-inch, Mid 2012)

Processor: 2.9 GHz Intel Core i7

Memory: 8GB 1600 MHz DDR3

Startup Disk: Macintosh HD

Graphics: Intel HD Graphics 4000 1024MB