Suddenly won't start up

I have a PC which I recently built (first ever), and I installed Windows 7 Home 64bit. The install was successful and for a few weeks I didn't really have any problems. When I first started transferring large files from a portable drive, I would randomly get BSODs on occasion. When i stopped transferring files, I wouldn't get any BSOD screens.
Ever since the other day, the PC would not turn on at all. I hit power, I get the BIOS telling me that it is loading Operating System, then I get to the screen where it says Windows didn't shut down properly, and it offers me the various Safe Boot and Normal Boot options. No matter which I choose, the display gives me no response after this screen; it just goes black.
How do I troubleshoot this? Any advice?

Thanks for the welcome! I went ahead and filled in my specs on the user page.

I also tried out a possible trouble-shooting technique: I removed my graphics card and plugged my monitor up to the inbuilt processor VGA. On starting the boot, I get to the same Safe Mode or Normal Mode screen, but this time my options are 'repair windows' or 'start windows normally.' I chose repair, and got no further. I tried start normally on the following boot, and got a bit further: this time it says 'starting windows,' but it freezes before the little icon animation is able load.

Thanks you guys for the input!!
I left the frozen screen for a while and eventually it actually did run Startup Repair. It said it couldn't repair the system. I clicked for details and one of the lines said Signature009: Bad Disk. Does this confirm what richnrockville was saying that the hard disk has a bad sector? Should I look for further confirmation of this before sending the drive back to Seagate? I would run the disk scan or the Seagate utility, but I can't complete the boot, and I don't have a second hard drive to run off.