Cpu 1 caller (panic error)

Could be lots of reason for this: filesystem got corrupted, hardware error.

I suggest you try holding down then powering on your system. keep holding

command + r

then try repairing the disk

command + option + r

for remote boot

I've only done it once and it was fairly quick if I recall correctly.

Command + r reads from the recovery partition. Could be a sign that there is a problem with the hd. Might want to consider getting an external drive and installing macos on it.

Try command + option + r

when you get tired of waiting. Might as well wait awhile longer.

Be advised that loading a new copy of the OS will destroy all your data.

Could take it by an apple store and see what they have to say.

Depending on what ports your machine has will determine what connectors you need for the external hd. usb 2.0 is kind of slow for booting.

I'd give OWC a call. 1-815-338-8685.

FireWire 800 + USB 3, + eSATA

&

save a little money interface:

FireWire 400 + USB 2.0

This web page lists both external harddrive types. You may need to scroll to the right to see both.

http://eshop.macsales.com/shop/firewire/1394/USB/EliteAL/eSATA_FW800_FW400_USB