Friday the 13th - Jason Goes To Hell

Halloween - Halloween III

A Nightmare on Elm Street - Freddy's Dead

Saw - Saw 4

Scream - Scream 3

The Texas Chainsaw Massacre - Part 2 with Dennis Hopper, one of the worst movies I've ever seen.

Alien - Wouldn't be fair to say since I haven't seen them in a very long time.

Predator - Alien vs Predator

Phantasm - been too long since I've seen them

Evil Dead - It's between parts 1 & 2, but I haven't seen them in so long. I love Army of Darkness though.

Hellraiser - Not sure which to pick, but I disliked every film after part 4.

Child's Play - Seed Of Chucky

Final Destination - I've only seen parts 1, 2, & 4.

Friday The 13th-jason x too unbelievable

Halloween-halloween resurection-a lot of the acting was bad

A Nightmare On Elm Street-part 6

Saw-part 7

Scream-3

The Texas Chainsaw Massacre-next generation

Alien-alien resurection

Predator-predator 2

Phantasm-not seen

Evil Dead-only seen the first

Hellraiser-only seen first and second

Child's Play-part 3

Final Destination-the final destionation

Bit of an older thread, but I was thinking of worst episode of a Horror anthology series per season for some variety.

I'm going to exclude remakes (If you were wondering, I would rate the remakes of the slasher series's to be the worst in their respective series, i.e. Friday the 13th, Halloween, and A Nightmare on Elm Street).

Friday the 13th- Part 2- I liked many of the films in this series, but this was my least favorite, although it was not an easy decision.

Halloween III- It was not bad as a film, but felt like a rip off because there was no Myers

A Nightmare on Elm Street- Part II: Freddy's Revenge by far (A New Nightmare was brilliant, I loved that movie, almost as much as the original).

Saw- Any after II (The first was brilliant and the second one was pretty good, but not near as great as the first)

Scream- Scream 3, but I loved all the films after one almost equally.

The Texas Chainsaw Massacre- I'll include the remake on this one. I consider the Texas Chainsaw Massacre: The Beginning to be my least favorite, since I have not seen the sequels to the original or the sequel/remake thing they released January of this year

Alien- Alien Resurrection

Predator- Predators

Phantasm- Have only seen the first one

Evil Dead- -tough call- but I guess I will choose Evil Dead II, but honestly the two sequels are equal, but the first is definitely the best in the series.

Child's Play- Child's Play 3

Final Destination- The Final Destination- this film was cheesy, cliche, and had bad acting, so it was quite terrible. Generally, this is a great series and one of the most original of the last decade, except this movie.

Hellraiser- Hellseeker- actually a number of the sequels were pretty good, especially III and Inferno with II being pretty good.

As far as Diary of the Dead, it was a great movie, perhaps my all-time favorite zombie movie.

Friday The 13th - Jason X

Halloween - Halloween 4 and above. Really only like I and II and I respect 3 as seperate from the series.

A Nightmare On Elm Street - Dream Master(4)

Saw - SAW V

Scream - Scream 3

The Texas Chainsaw Massacre - The Beginning

Alien - Alien: Resurrection

Predator - Alien Vs. Predator: Requiem

Phantasm - Oblivion

Evil Dead - Army of Darkness- love them all but this one wasn't the best

Hellraiser - Hellseeker

Child's Play - Seed of Chucky

Final Destination - honestly hate all of them

The sequels are definitely worth a look if you liked the first.

Trying to think of some more series I can add, I'm sure I've missed some. A lot of the old Universal and Hammer films leap to mind.

Friday The 13th Part 8: Jason Takes Manhattan: Just terrible!

Halloween: Anything after part 3. They're all equally bad

A Nightmare On Elm Street Part 2: Sort of funny to watch, but it was a complete disaster.

Saw 2: Most unlikable characters ever assembled in any movie

Scream 2: Any movie with Jerry O'Connell can't be good

The Texas Chainsaw Massacre III Leatherface: Such a disappointment follow up to the classic Part 2

Alien Resurrection: This movie had zero thought put in to it! The script was nothing more than a bunch of silly predictable catchphrases strung together as dialogue. And the acting was just terrible, with almost every character trying to be overly hip and cool. Not to mention that the aliens weren't scary or menacing in the least.

Predator AVPR: I'm just assuming this because the three times I"ve tried to watch it, I was dead asleep before the half way mark of the movie

Phantasm: Watched them, but really can't recall them

Evil Dead: Good movie, but it doesnt compare to the II or army of darkness

Hellraiser: Any of the Hellraisers past part 3 were all pretty terrible

Child's Play: Never watched them

Final Destination 3: When you kill people off in a movie, you should at least care that they're dying.

*Some franchises not mentioned:
- Leprechaun
- Romero's Dead Series
- Zombi
- Amicus trilogy flicks
- Puppetmaster

A funny addition that comes to mind are SyFy's original movies. They're all so terrible and it could be fun picking them apart :D