I downloaded Windows7 "freeware/utils" (dozens) & accidentally downloaded Windows7 itself! Are the feds coming?

No, especially not if you deleted it. This isn't a major incident so the most that will probably happen is you will get a letter in the mail from your internet service provider warning you that you must delete the program or your internet service will be shut off because they do monitor it and downloading something like that would exceed bandwidth which is something they pay close attention to. It's how they catch illegal downloaders. But you should be just fine, especially since you deleted it immediately.