That’s still my favorite.
Hedley Lamarr: [to himself] A sheriff! But law and order is the last thing I want. Wait a minute… maybe I could turn this thing into my advantage. If I could find a sheriff who so offends the citizens of Rock Ridge that his very appearance would drive them out of town.
[looks into the camera]
But where would I find such a man?
[pause]
Why am I asking you?
It’s just the breaking the 4th wall that I love. Much the same when Korman’s talking about being nominated for the Oscar.
“Piss on you; I’m workin’ fer Mel Brooks!”
Not the face!
… and methodists!
Could you repeat that?
I was wondering how long it would take before someone mentioned the campfire scene.
Oh, and
“They said you was hung!”
“And they was right!”
“'Scuse me while I whip this out.”
Sing us a good ol nigger work song!
“I get no kicks from champagne…”
Got to be the opening scene, with (can’t remember the actor’s name – my uncle claims he knew him slightly) Lyle dancing around like a Kansas City Faggot (the team, not the sexual preference).
“Dock that chink a day’s pay for nappin’ on the job!”
“Well, my grandmother was Dutch…Just trying to help you out!”
In the 38 years since it was released, most of the profanity and sexual inuendo have become mainstream, but the N-word is a giant no-no.
Another 100 years and Blazing Saddles will need footnotes. 
There are too many funny lines to mention without quoting the whole script, but “No, Mongo straight!” and " … But not the Irish!" are great lines.
I lost my wallet while watching Blazing Saddles in the theater. I swear it was during the bean scene because I was laughing so hard. Had to go back to the theater to get my wallet, which was under my seat. I’ve kept my wallet in a front pocket ever since.
Never fails to crack me up, especially with Gene Wilder’s great delivery.
You could just post the script as a great line.
One of my favorites, not fully mentioned, is:
Ditto??! You provincial putz.
There there, it’s just a man and his horse being hanged.
The rape jokes are not exactly acceptable these days either. Which I think is why they make me laugh so much.
Taggart: I got it! I got it!
Hedley Lamarr: You do?
Taggart: We’ll work up a Number 6 on ‘em.
Hedley Lamarr: [frowns] “Number 6”? I’m afraid I’m not familiar with that one.
Taggart: Well, that’s where we go a-ridin’ into town, a-whompin’ and a-whumpin’ every livin’ thing that moves within an inch of its life. Except the women folks, of course.
Hedley Lamarr: You spare the women?
Taggart: Naw, we rape the shit out of them at the Number Six Dance later on.
Hedley Lamarr: Marvelous!
*“Depends on how much vitamin E I can get my hands on”
“Man them shnitzengrubens will wipe you out!”*
Everything from the waist down is kaput.
Bart: Mornin’, ma’am. And isn’t it a lovely mornin’?
Elderly Woman: Up yours, nigger.
Count Basie’s orchestra in the middle of a desert.
Mel Brooks has explained it something like this: The new sheriff is a negro, so there must be negro music played and the best he could think of was Count Basie. However, it would be very illogical to hear music in the middle of a desert if the orchestra wasn’t there as the gramophone was not yet invented.