Oh noes not at all. There are quite a number of games based (directly or otherwise) on movies that were great. To name but a few:
http://www.mobygames.com/game/lion-king
http://www.mobygames.com/game/lord-of-the-rings-the-battle-for-middle-earth
http://www.mobygames.com/game/windows/blade-runner
http://www.mobygames.com/game/n64/star-wars-episode-i-racer
http://www.mobygames.com/game/chronicles-of-riddick-assault-on-dark-athena
http://www.mobygames.com/game/super-star-wars

I quit playing anything I don't like, so I can't remember any bad ones in particular. To be honest, though, many of the games I dislike are perfectly fine games in many aspects, it's just that I didn't like playing them; so, it wouldn't be fair to call them the worst games.

But I think the worst game ever would be something which is just plain buggy as shit, and thankfully I haven't encountered anything like that yet.

Do not miss the Tree Simulator 2013

Pool of Radiance: Ruins of Myth Drannor

Hooooooorendous.

You forgot Aladdin on the Sega Megadrive!

Oh yes, I've played that a couple of times on an emulator :)
I was going to add it, but got hung up on The Little Mermaid NES release, which I decided to remove.

I still hold Sherlock Holmes Mystery of the Mummy to that place.. But that is because i got litteraly sick with the 360 lens view, motion sickness of sort.. Turned me white as sheets and I was crying for fresh air, that and the game is an insulting bunch of obscure "puzzles" thrown together in a damned Egyptian museum of sort.

I remember breaking quite a few joysticks on my Atari when I got the ET game. Granted they were lousy joysticks, but the game was horrible.

This is just my subjective personal opinion, but to me the worst video games ever made are the ones that try completely to be a Hollywood movie. Everything from the pacing to the movie-wannabe background music to the shakycam camera (like a JJ Abrams movie), I strongly dislike such movie-wannabe "games".

Ladies and gentlemen, behold the abomination that is
Crazy Bus!!!

Star Control 3 was disappointing but not the worst. Atari Pac-Man was terrible. Custer's Revenge has to be the worst.

If I wasn't a Trek fan, I would have bailed. I was disappointed. Hope you enjoy it more than I :D

You're right about that one. Wait! I also loved Star Wars Pit Droids... :)

It was cool, sure, especially for an Atari game of that time. But no soundtrack could make that gameplay "worthwhile"...