Toho Kingdom

1. Gojira

2. King Kong vs Godzilla

3. Mothra vs Godzilla

4. Ghidorah

5. Son of Godzilla

6. Godzilla 1984

7. Godzilla vs Biollante

8. Godzilla 2000

1. Godzilla, King of the Monsters!
2. King Kong vs. Godzilla
3. Mothra vs. Godzilla
4. Monster Zero
5. Son of Godzilla
6. Godzilla vs. Mechagodzilla
7. Godzilla vs. Biollante
8. Godzilla 2000

Man, this is harder than I first thought.

- Gojira
- Godzilla vs Mothra
- Ghidorah: The Three Headed Monster
- Destroy All Monsters
- Godzilla vs Biollante
- Godzilla, Mothra, King Ghidorah: Giant Monsters All Out Attack
- Godzilla Against Mechagodzilla
- Shin Godzilla

Gojira 1954
King Kong Vs Godzilla
Godzilla Vs SpaceGodzilla
Godzilla 2000
Godzilla Against Mechagodzilla
Godzilla Tokyo S.O.S
Godzilla: Final Wars
Shin Godzilla

1. Godzilla/Godzilla, King of The Monsters
2. Mothra vs Godzilla (1964)
3. Godzilla vs Biollante
4. Godzilla vs Monster Zero
5. Godzilla vs Gigan
6. Godzilla vs Hedorah
7. Godzilla vs Megalon
8. Godzilla's Revenge

Oh, man, I love this topic!! I probably make a YouTube video for it, and I'll give a shout out to the creator of the thread!

I would have to say these 8, in no particular order:

1. Gojira - I mean, it was the first one ever. And the best, in my opinion. I have to keep it.
2. Godzilla vs MechaGodzilla (Showa) - This one is so fun to watch, plus it's in my top 10.
3. Godzilla: Final Wars - Mostly the same reasons as 2, but it was also supposed the last Godzilla movie ever, and it was the 50th anniversary special.
4. Godzilla (2014) - While this isn't my favorite, we would need it to show that an American Godzilla movie can be done right.
5. Shin Godzilla - Again, in my top 10, and the japanese reboot of the king of the monsters after a 12 year absence.
6. Godzilla 2000 - I love this one, and it was a reboot.
7. GMK - A fan favorite, as it is one of mine.
8. Destroy All Monsters - ITS DESTROY ALL MONSTERS!!

This was super hard to choose, but I did mine based on which ones I liked, which ones were milestones in the franchise, and fan favorites.

Just a periodic in-thread reminder; this is the original 29 films, from 1954-2004. The safety of 2014 and Shin is already assured, since they are not among the at-risk entries- so that frees up 2 more slots on most lists!

1. Gojira. Original Godzilla movie has to be saved.
2. Godzilla vs Mechagodzilla. Great fight, shows Godzilla as a badass. MechaGodzilla is my favorite opponent
3. Godzilla vs Destroyah. Fun but serious movie. love how 90's it feels and looks Lots of good fights.
4. King Kong vs Godzilla. Pits the two biggest movie monster of all time against each other. What's not to love?
5. Destroy all Monsters. 60's Classic. Shows off all the Godzilla cast. Has a big time feel.
6. Godzilla against Mechagodzilla. Gotta have a Millennium film, love how even the fight is.
7. Godzilla vs Mechagodzilla 2. Again I love Mechagodzilla. The fights are good. Helps set up for Destroyah.
8. Godzilla vs Spacegodzilla. Love the end credits music.

Choosing mine, I tried to thing of examples of what to "preserve" as we are saving these films.
***This is not inherently a reflection of what I believe are the 8 best of the franchise.***
I explain myself briefly for each one.

1- Gojira. Must preserve the classic.
2- King Kong vs. Godzilla. One of the first "cross-over" films between big licenses. Maybe not the best example of it, but important to remember.
3- Destroy All Monsters. A prime example of what you can do with a large kaiju roster. Great effects, and a lot of fun. One of the more definitive Godzilla films.
4-Godzilla vs. Hedorah. Saving this as it's a film with a STRONG message about pollution and saving the planet. Not, in my opinion, one of the best, but definitely an important film and worth preserving for future generations.
5-Return of Godzilla. The dark, serious tone makes a come back here, and I love it. But it's also a socially important film, showcasing the tensions of the Cold War and the tense world relations at the time. An important film to preserve.
6- Godzilla vs. Biollante. Significant in that it shows what genius can do when corrupted by the pain of loss, but also a film that shows the dangers of bio-warfare.
7. Godzilla vs. Mothra. Another Godzilla film with an ecological message to it, though not as poignant as Hedorah. Still, an important message about protecting the earth and each other.
8. Godzilla, Mothra, and King Ghidorah: Giant Monsters All Out Attack. My personal favorite Godzilla film, and the film I generally show people when introducing them to the franchise. So consider this a "personal" pick for me.

Easy.

Ghidrah the Three Headed Monster

Mothra vs. Godzilla

Godzilla King of the Monsters

Godzilla vs. Monster Zero

King Kong vs. Godzilla

Gojira

Son Of Godzilla

Destroy All Monsters

1. Gojira/Godzilla, King of the Monsters (Should have been a default answer IMO.)
2. King Kong vs. Godzilla (One of the most culturally significant G-films of the entire franchise.)
3. Destroy All Monsters (A classic film from the golden age of the era, originally intended to be the final film of the franchise.)
4. Godzilla vs. Hedorah (My personal second-favorite film, a trippy, experimental, yet effective entry in the series.)
5. Godzilla vs. Mechagodzilla (I must include the final two films in the original Showa series. A brief return to the darker, more serious roots for the franchise before the 9-year hiatus. Plus, good god that soundtrack! Couldn’t ever live without it.)
6. Terror of Mechagodzilla (My favorite Godzilla film ever. I’d include the version with the extended prologue, as that includes scenes from MvG, IotAM, and Godzilla’s Revenge that would otherwise be “lost”.)
7. The Return of Godzilla (Not my favorite Heisei film - that would be vs. King Ghidorah - but essential as the sequel to the original film.)
8. Godzilla: Final Wars (Not only was it the 50th anniversary film, but the opening montage features bits of the movies that couldn’t be saved in this list, so at least they’d still exist in some brief form!)

Hey, quick question. Would the original trailers for all the movies still exist? Or am I thinking too deep into this hypothetical situation?

Godzilla ('54), Godzilla Raids Again, King Kong vs. Godzilla, Mothra vs. Godzilla, Ghidorah the Three Headed-Monster, Son of Godzilla, Destroy All Monsters, Godzilla vs. Hedorah

Not necessarily my favorites (At least not GRA), but tells a mostly coherent story when ended with DAM. Hedorah is in there being a favorite of the 70s films.

Godzilla
KKvG
MvG 64
Ghidrah
Monster Zero
SoG
Hedorah
Biollante

Whoa it's all of the objectively good Godzilla films.

Awww what the heck? Why not?

1. Ghidorah, The Three-Headed Monster

2. Ebirah, Horror of the Deep

3. Godzilla Final Wars

4. Invasion of Astro-Monster

5. Godzilla vs. Mechagodzilla

6. Son of Godzilla

7. Godzilla vs. Mothra

8. Godzilla vs. Gigan

1 Gojira: Needs no introduction.

2 King Kong vs Godzilla: Too great a crossover to be missed.

3 Mothra vs Godzilla (1964): A great film that shows the pinnacle of kaiju golden age special FX.

4 Ghidorah the three headed monster: The rushed but good sequel, bringing good ol Giddy to the scene.

5 Godzilla vs Monster Zero: A film that is better than most give credit for, creating more fluid special FX shots than GTTHM and still having high quality monster suits (The Godzilla suit in this film looks better here than it & others would look later on).

6 Godzilla vs MechaGodzilla (1974): The best of the 70s films in my opinion, filled with plenty of monster fights and bringing some seriousness back into the series, and giving us a great adversary in the form of MechaGodzilla. (That & the soundtrack is far better than ToMG's, I'm not sorry. )

7 Godzilla 2000: A cool looking Godzilla design(before they made it too bright looking in Megaguirus) and a brand new foe face off at the turn of the century.

8 Godzilla against MechaGodzilla: This movie has a great looking redesign of MechaG and an award winning soundtrack.

1. Godzilla (1954)
2. Godzilla Raids Again (1955)
3. King Kong vs. Godzilla (1962)
4. Mothra vs. Godzilla (1964)
5. The Return of Godzilla (1984)
6. Godzilla vs. Biollante (1989)
7. Godzilla vs. Mechagodzilla II (1993)
8. Godzilla vs. SpaceGodzilla (1994)

All of these need a 4K makeover, ESCPECIALLY KING KONG VS. GODZILLA.

1. Godzilla (1954)
2. Mothra vs. Godzilla
3. Ghidorah: The Three Headed Monster
4. King Kong vs. Godzilla
5. Destroy All Monsters
6. Godzilla (1984)
7. Godzilla vs. Destroyah
8. Godzilla 2000

1. Godzilla (1954)

2. The Return of Godzilla (the Japanese version)

3. GMK

4. Godzilla Vs. Biollante

5. Godzilla Against Mechagodzilla

6. Godzilla 2000

7. Godzilla Vs. Mechagodzilla (1974)

8. King Kong Vs. Godzilla (mostly for historic significance in the character's history rather than personal favoritism)

Godzilla
Mothra vs Godzilla
King Kong vs Godzilla
Invasion of the Astro-Monster
Godzilla vs King Ghidorah
Godzilla vs Biollante
Godzilla vs Destroyah
GMK

These aren't my eight favorite films, but they're the ones I think represent each era well and are all entertaining.

1- Godzilla 1954 (The Alpha)

2- Godzilla: Final Wars (The Omega)

3- Godzilla Destroy All Monsters

4- Godzilla vs King Guidora

5- Godzilla vs Destoroyah

6- Godzilla vs Biollante

7- Godzilla, Mothra and King Ghidorah: Giant Monsters All-Out Attack

8- Mothra vs Godzilla