I have the core important things backed up in the main if all goes to fluff again.
Not meaning to be an IT ambulance chaser..... but if it turns out its your HDD thats borked I have recent 250 and 500GB 2.5" hdd's that could be yours for a very competitive few feck alls...
If it's under warranty I would take it straight to a Mac Store, rather than have your in house tech-heads have a go at it.