Oh boy, if it was trying to encrypt data and failed mid-procedure I think it's safe to say that some or all of the data on your phone's storage is lost. I did happen to find a procedure on an XDA Developers forum that is supposed to help reset your phone. The only issue is that it assumes you have rooted your phone. Here's the link http://forum.xda-developers.com/showthread.php?t=1447303.
Let me know if you have a problem with the reset procedure.