iPhone blacked out

Hey all, I'm a bit new here and after unlocking my phone and having 3 months of great usage it's died....

I had some apps on it like iToday which were causing some problems, then randomly it froze up, so I held the lock button and Home button and it tries to restart....and then its stuck at the Apple icon for another 2 hours and it keeps turning on and off but it still won't turn on.

I can't reset it iTunes either, it says "unknown error" when it tries to prepare it for restoration...

Help