First thing: make sure there are no disks in any of your drives (optical or otherwise)...you want to make sure your computer isn't trying to boot to something other than your HDD.
If that doesn't work then right after POST try and hit F8 repeatedly until you get a Windows startup options screen...the option to go into Safe Mode should appear; try that one.
If no-go there then I would go with Spikey's idea and boot to a CD-ROM just to make sure you can do so. If you have a DOS boot disk of some sort then running a chkdsk on your boot HDD would be a good idea...just make sure your DOS boot disk can read NTFS.
If you can't even get that far then something is likely wrong with some component in your computer. I would first try and start disconnecting components (unplugging from power / removing when needed) one by one, restarting after each. When you get something past that black screen you'll likely have found the culprit. Given the nature of the errors I would start with your HDDs, one at a time, and go from there on to other components. RAM might be a good place to go next.
Also, as it sounds like you have other computers around to work from, you can always take your C drive out and connect it to another machine; from there you can see if the same problem happens on that machine when trying to boot from that HDD. You can also run a CHKDSK on it from there to see if any errors are found that should be fixed.
Ultimately, though, before trying to fix any OS errors (via something like a repair install of Windows) I would strongly advise to check the disk for bad sectors. Normally if the OS was the culprit here we'd see some kind of message from Windows that a file is missing or damaged, or some other error message. When you get no action at all then that smells of a more hardware-oriented problem, although of course not necessarily.
