If you break up a RAID 0 array, you will lose everything.
RAID 0 is typically 2 hdds connected together so that the hardware sees them as one disk. The OS doesn't care where the data is written to and data is written to each disk in turn, (note, it is not written to 'both' disks identically), so that, for example, a document file will be stored in bits and pieces on to the two drives, some on one and some on the other.
So, breaking up the array into two separate disks, and you will have two disks, each with different data on it, in an unreadable format.
That means you would have to reinstall the OS onto one of the drives, (after a reformat), and also reinstall all other software. Of course you should always backup the personal data and files that you are working on or have stored on the array before making any changes. Losing an OS and programs, whilst a pain, is relatively easy to overcome. But losing all you work is not.
In addition to that, and I am certainly no expert, if the RAID is setup via the BIOS with RAID controllers on the motherboard, changing that to non-raid, (just normal SATA drives), is a steep learning curve, as I found out myself when I moved from a RAID 0 2 x SSD configuration on my Vista rig to a normal single SATA drive with Windows 7 installed. See my own thread in the link below;
You will see I needed extensive expert advice.
So all in all I tend to agree with Kees here. From your post I gather you are a professional who uses Photoshop extensively for work. You may find it much easier to go for a new machine, set up as you require. Also, personally, I would stay away from SSDs. There are still issues with SSD file delete management, which makes SSD longevity a problem.