No reason to suspect the hard drive is about to fail. Windows not loading is not a symptom of HD failure. - It reaches the first stages off booting, indicating the problem is elsewhere.
It depends on type of failure, if it's getting bad blocks then it could still load the boot loader and fail further on. I've just RMA'd a laptop drive with these exact symptoms. When I used a USB caddie Win7 wanted to format the drive but fortunately Recuva managed to read all the user data off. ESTOOL found a lot of bad blocks when it did a surface scan, in the original laptop it was still getting to the boot menu and then crashing.
There can be many other reasons for the symptoms (I'm not trying to leave myself wriggle room!

), but getting a backup of the data should be a priority and the drive can be verified in the process. That's why I suggested an emergency type of CD to boot from so other components can be tested as well.