We'll need more information than that to help. Tell us exactly what
happens when you boot and what modes you've tried.

John.

Did you ever get this issue resolved?  This has happened to me with 2
computers.  It asks if I want to boot in Safe Mode, Last Good Configuration,
or Normal Mode, however, no matter which one I choose, the computer will not
re-boot and I end up back to this screen asking which mode I want.  Will not
let me into system restore either, although this is listed as an option.  I
had to use system recovery and start over from scratch with both computers.  
Is this what you also experienced?