Unable to boot up

So I updated to 10.9.2 as I recall, and I restarted perfectly fine, but that day my laptop was being particularly slow and laggy, and so I restarted it to see if that would help. When it booted up again, there was a grey bar under the apple sign after the swirling and the bar very gradually filled. At about maybe 1/20th of the bar being full my laptop would just shut down. I've tried booting it multiple times but each time it would just do the same thing. I reset SMC and PRAM but that didn't help. I booted up in recovery mode to try repairing disk in Disk Utility, but about a quarter of the way in it said repairing failed or something I don't remember. I do not have a Time Machine back-up.

At the moment I'm on my Windows 7 partition which is working fine, so I can transfer files from my mac partition onto a harddrive through the W7 partition. So what I can do is grab what I need and then reinstall Mavericks. However, it would be best and much easier if I could have my laptop exactly the same so should I take it to the genius bar?

My priority is my files and I don't want to lose them and I'm worried that the guys at apple support will do whatever they do with the firewire cables or I don't know and say that my files are unrecoverable because atm I can still access my files through my bootcamp.

I know I haven't provided much information but if there are any other things I can do at home or any other diagnostics help would be much appreciated.

Thanks