while walt is disrobing...
"you're keepin those on, right?"

When Walt asks him "Why are you all blue?"

My most recent favorite:
When they're out in the desert, with Saul...and Jesse starts spatting him, for taking off his mask!
TOO funny! =D

First episode

Jesse: Some straight like you, giant stick up his ass, age what - 60? He's just gonna break bad?
Walter: I'm 50.
Jesse: It's weird is all, okay? It doesn't compute. Listen, if you've gone crazy or something...I mean, if you've...if you've gone crazy or depressed, I'm just saying...that's something I need to know about. Okay? I mean, that affects me.

First season, last episode, hilarious part I think
Jesse: A junkyard? Let me guess, you picked this place?
Walter: What's wrong with it? It's private.
Jesse: This is...This is like a...a non-criminal's idea of a drug meet. This is like, "Oh, I saw this in a movie. Ooh, look at me."
Walter: Yeah, so...so where do you transact business? Enlighten me.
Jesse: I don't know. How about Taco Cabeza? Half the deals I've ever done went down at Taco Cabeza. Nice and public. Open 24 hours. Nobody ever gets shot at Taco Cabeza. Hell, why not the mall? You know, wait at the Gap. "Hey! It's time for the meet!" You know, I'll put down the flat-front khakis, head on over, grab an Orange Julius. Skip the part where psycho lunatic Tuco, you know, comes and steals my drugs and leaves me bleeding to death.

And probably my all time favorite, and one of my 2-3 favorite scenes in the show is when Jesse discovers Walt has cancer, and that is why he is cooking .Love this scene

Jesse: When were you going to tell me?
Walter: Tell you what?
Jesse: Cancer. You got it, right?
Walter: How did you know?
Jesse: [pointing to Walter's chemo mark on his chest] My aunt had one of those...dots on her to target the radiation. What is it, in your lung? I'm your partner, man. You should have told me. That's not cool, okay? Not at all. What stage are you?
Walter: 3-A.
Jesse: Gone to your lymph nodes.
Walter: Your aunt...How bad was she when they caught it?
Jesse: Bad enough. She didn't last long.
Walter: How long?
Jesse: Seven months. I get it now. That's why you're doing all this. You want to make some cash for your people before you check out.
Walter: You got a problem with that?
Jesse: You tell me. You're the one that looks like you just crawled out of a microwave.

1st Fav Scene: At Tio's house, when Walt and Jesse are arguing over how to kill Tuco, and who will do it. Jesse wants Walt to do it, and Walt waves the flyswatter around and says With what? This?".

2nd Fav Scene: Walt scolding Jesse to get out of bed, and Jesse is going for his bong, and Walt grabs it, saying something like "Oh no you're not!". Another great moment between daddy Walt and son Jesse.

Agree - Definitely the most defining moment so far, is when they are out at Tio's house being held by Tuco, and they briefly argue over how to take out Tuco and who should be the 'sacrificial' hero to get them out of this mess...

The other part of the scene at Tio's house is Jesse volunteering Walt to do the killing because it's logical according to Jesse - Walt's old and going to die anyway. Walt gets pissed off when Jesse says that. LOL

well it has to be the first time they go to sell to tuco in the junk yard when jesse said why couldent we have met in the mall people dont get killed in the mall priceless

Two times come to mind. First is firs season, when Walt finds out that Jessie just dumped the hydrofluoric acid into the upstairs bath tub to dissovle the body of the druggie that they had killed, and as Jessie is asking Walt why he (Jessie) shouldn't have done this, the gorey mess comes falling thru the ceiling. Walt says calmly, "well, there's that...."

Second this season when Walt is going to make the poison Rison from soybeans to poison Tuco, and Jessie says something like, "come on, we're going to kill him with rice 'n beans?"

Therre are really too many great moments to mention.

Well some people can suffer adverse gastronomic effects from rice 'n beans, LOL. I don't remember Jesse saying that, but it's classic! Thanks for the reminder MHJim.

All of the scenes where you can tell that Jessie and Walt (minus obvious sentimentality) really do give a damn about each other.

I agree with MhJim with the scene about the bath tub scene and walt trying to explain why he shouldn't have used the bathtub and then all of a sudden the desolved body parts comes raining down on them.. Priceless... and walt standing there looking at Jessie .."like when are you going to listen to me when I say dont do something?". Priceless. I laughed so hard, tears were rolling down my face!

2nd scene when they are stranded out in the middle of nowhere with the dead battery in the RV and after making lbs of the blue meth.... Walt comes up with the make-shift battery...unbelievable! Can chemistry be that good??????

Walt and Jessie are the new 2000 millennium version of the "Odd Couple", always bouncing off of each other with uncanny humor!!