Instructions for uninstalling can be found on page 37 of the +*Parallels Desktop for Mac User Guide*+, which is found in the same folder as the Parallels application on your hard drive.
I believe uninstalling Parallels removes all the Windows files associated with it, however if you have created a partition for Windows initially in BootCamp and simply use Parallels to run it sometimes then you may have to remove the partition using the BootCamp Utility which can be found in your utilities folder.
Thanks all,
It turns out that the .hdd image is not uninstalled. But it worked out cool because I just dropped the .hdd disk image on a dvd which will speed up the process next time I want to have windows on the machine.