How to get toshiba laptop to boot up?

I have a Toshiba laptop Satellite model #L455d-s5976 bought Christmas of 2011 so its just a little past its warranty I has been working fine until two days ago. I shut it off like normal but now it wont start up. It keeps saying windows cant load maybe do to last program or hardware downloaded. I have tried all the normal and abnormal sutff. Held down zero, f8 f10 f2 tried safe mode everything. It will come up with the safe mode menu but when I try to load safe mode, the drivers list comes up and it goes to a black screen with jsut the arrow(mouse pointer) and thats it. This is what it does no matter what i do. I can go to different start up options and it says loading windows but always goes black and stops.I did not download anything last time on it but have been getting a message at start up about the ntds needs to be checked. It would check and restart and do it over and over unless i hit any button. It had been doing this for a couple of weeks but have had no problem until now. I hit f12 and came up with a screen Path/windows/system32//boot/winload.exe then further down says /minint/redirect rdimageoffset+8192 rdimagelength=3161088 RDPATH=multi1ti(0)disk(0)rdisk(0)partition(3)/sources/boot.wim. Then at the bottomjust says enter =submit. I hit enter once before and same ending blackscreen of death. I do not have any back up disk and computer did not come with any. Is there a place i can download the OS disk or any ideas on what to do? any help would be great. Thanks so much.