What's the ending?

OK this is a spoiler. But it has been several years since I watched it.
.
>
>
>
>
>
>

Ed's mom is brought back to life, and the only way to kill her is to cut her head off and bury it seperate from the body. Of course the head still talks after it is taken off her body. Then the company rep feels bad about the bad experience that he has had with his mother, and so he wants to do something nice for him so he brings his father back from the dead. and that's basically the end. the movie starts with the guy on trial for killing his mother, and then at the end he is found innocent because she was technically already dead when he cut her head off.