There are many fallout dialogues made, which one's of those are your favorite?

" War. War never changes. " Obviously ^^ !
Although I like FO4's

Fallout 4 had a good amount of lines there, but my favorite is

"Ad Victoriam!"

In New Vegas...hmmm...its from Ulysses;

"No need to destroy the Bear. Just cut its throat."

"If war doesn't change, men must change, and so must their symbols. Even if it is nothing at all, know what you follow, Courier..."
Ulysses.

Pretty much the entire scene with Danse and Maxson. Amazing quest, brilliantly voice acted and still one of my favourite quests in Fallout purely because of the dialogue.

"Millions, perhaps even billions, died because Science outpaced Man's restraint."

Because why not:
Patrolling the Mojave almost makes you wish for a nuclear winter.

"Duty, honor... courage... Semper Fi...." - Frank Horrigan

"War... war never changes. Men do, through the roads they walk." - Ulysses (Fallout New Vegas)

"So go to the building and take this fucking platinum chip whit you"
- Caesar

I laugh so hard at that one. Still my favorite of the entire franchise.

"Please, assume the possition"

Fisto is love, Fisto is life.
And also everything that Liberty Prime says.

From New Vegas, speaking to George after returning from Nellis; "Jumpin' Jesus on a pogo stick! You're the first one to make it through alive, let alone manage a return trip!"

"What in the goddamn...?" - Benny

"Thesis and antithesis. The Colorado River is my Rubicon. The NCR council will be eradicated, but the new synthesis will change the Legion as well... from a basically nomadic army to a standing military force that protects its citizens, and the power of its dictator." -Caesar

"This crater looks it's been tag-teamed by giant fuckbots" from Old World Blues.

Even though I don't like FO4 that much but some of the sarcastic dialogues are pretty funny and those are my favorites. Especially the one about penis size with that old minutemen woman after taking the castle back.(i forget the details.)

I have a lot of favourite lines so I decided to go with the first one that popped into my head when visiting this page, so here it is:

"Hey, you not ghoul. How come?"

"Take Drugs! Kill a Bear!" - White Bird (Honest Hearts)

"They try to put their stake in everything they see. Nobody's dick's that long, not even Long Dick Johnson, and he had a fucking long dick. Thus, the name." - Rose of Sharon Cassidy (New Vegas)

[ LITERALLY ANYTHING SAID BY LIBERTY PRIME OR DOCTOR KLEIN ]
"WHAT ILLOGIC IS THIS?! KEEP YOUR FILTHY PENIS-TIPPED FEET OUT OF OUR LABS AND SECRETS!"
"WHAT IS THIS, A HIGH SCHOOL SCIENCE FAIR?! GET YOUR ACT TOGETHER, YOU'RE MAKING US LOOK LIKE A COLLECTION OF ROUND-EARTHERS!"
"ATTENTION: BIG MT. THIS IS AN URGENT MESSAGE. IF YOU HAPPEN TO SEE A GECKO... ECKO. ECHO? ECH-O. ECHOOOO. ECHOOOO."
"DEMOCRACY IS... NON-NEGOTIABLE!"

Not going to quote the entirety of both speeches, but I'm particularly fond of the exchanges between the Vault Dweller and the Master, and the Courier and Caesar, when detailing their thought processes and beliefs. Hearing Caesar talk about Hegelian dialectic blew my mind. Never thought a game would go into something like that.

Also, Harry in F1 also amuses me. Harold too, of course. Original Harold, that is.

VD: "How did you survive?"
Harold: Didn't. Got killed."

Cracks me up every time.

One of my favorite quotes comes from fallout 4:

"The thing about happiness is that you only know you had it when it's gone. I mean, you may think to yourself that you're happy. But you don't really believe it. You focus on the petty bullshit, or the next job, or whatever. It's only looking back by comparison with what comes after that you really understand, that's what happiness felt like."
-Kellogg