This is an extremely straightforward process, it sounds like there is a problem with your windows 7 disc.

I do this process all the time, it's as simple as:
-Partition drive with bootcamp assistant
-Choose to reboot from windows install disc in bootcamp
-Run windows install

So I would reinstall OS X like Simba said, install all the updates and get the latest version of bootcamp/bootcamp drivers from apple.com/downloads if they don't automatically update, then try again. You may want to make sure all is well with your disc by trying to boot another machine from it.