Maybe not the greatest, but he's the most entertaining. My favorite is definitely Guy! 
 

@Silkcuts said:

@Billy Batson said:

Tbh it's Hal but Sodam Yat will be the greatest. 

BB

With the DCU going away from Alan Moore Mythos, I am likely to believe Yat will not be the greatest since Alan Moore created him in Tygers, which was first printed in Tales of the Green Lantern Corps Annual #2 in 1986.  Didn't Mogo die as well?  Another Moore creation.

Yeah I read the story. So is Yat leaving the DCU? Haven't been keeping up with the revamp. 

BB

@Silkcuts said:

@Billy Batson said:

Tbh it's Hal but Sodam Yat will be the greatest. 

BB

With the DCU going away from Alan Moore Mythos, I am likely to believe Yat will not be the greatest since Alan Moore created him in Tygers, which was first printed in Tales of the Green Lantern Corps Annual #2 in 1986.  Didn't Mogo die as well?  Another Moore creation.

Where did you hear this?

More and more, I find it to be John Stewart, hands down.  For the longest time, from reading Blackest Night and the preceding issues leading up to it, followed by Brighest Day, I used to think of Hal Jordan being the best, but now, after giving thought and consideration, it has to be John Stewart.  Can't stand Kyle Rayner.

BATMAN!!

Kyle Rayner

Ryan Reynolds

John Stewart.

I like Kyle the most(the most creative and unique and in terms of coolness I think he's the coolest GL)
 
 I'm sure Hal will win the popularity vote... overall
 
While classic GL no doubt Alan Scott

My favorite is Kyle,i like his personality more and I'm a fan of his constructs but the greatest of all is Hal Jordan.

Hal Jordan. We wouldn't even be discussing this without him.

Kyle Rayner :-)

yea man gotta give it to Hal

@Batmarcus: Either Kyle Rayner or Sinestro!

@Samimista said:

John Stewart and Kyle Rayner

I vote for Kilowog or Mogo.

what about g'hu an almighty green lantern who is so cool

Between Kyle Rayner and Hal Jordan.

Hmm, in my opinion there are only 3 (Possbly 4) that canever be considered. In order, say its:

1. Hal Jordan

2. Kyle Rayner

3. Abin Sur

Really, these 3 are just SO well known hat I feel it should be self-explanatory. People might disagree obviously due to personal tastes and different classifications of the term "Greatest", but I think everyone can agree these 3 alway deserve to be considered. Now, for my possible 4th pick:

4. Sodam Yat

This is entirely based off Alan Moore's ancient prophecy from Tales of the Green Lanern Corps (Can be found on Amazon) that Yat would be known as the greatest green lantern. During the Sinetro Corps War, I honestly thought they were finally getting ready to put Moore's prophecy into effect, but they haven't. In fact, it seems they're doing the opposite with the death of Mogo and Sodam's loss of the Ion entity.

Sinestro. All others are inferior.

Kyle, it's not even close. 

well according to the comics it is Hal...

but i mean there are soo many cool green lanterns..But id have to go with Kyle Rayner , i mean for a guy who just happened to walk out of a bar an artist, and then become a green lantern and take on the responsibility of restoring the corps, becoming host to ION, and currently in the new 52 he was able to wield ALL the rings..and that act even stunned the guardians! plus if it wasnt for kyle i probably wouldn't have event stumbled across green lantern comics! so not only is kyle is my favorite but he is arguably the best of them all! but there are alotta cool lanterns out there, kilowog, guy gardner..oh and definitely john Stewart has to be up there. he does what he has to get his job done..even if it means killing off his teammates (unfortunately about 3 times to many though :/)

and currently i think his series : Green Lantern: New Guardians is the best of this new 52 by far! :D

Hal. Nuff said.

#3

For the trials & errors he went through becoming the greatest Green Lantern that has ever placed a ring on their right hand while reciting the oath, I believe Hal Jordan of Earth fits the part. As Sinestro was labeled the greatest Green Lantern ever lived, he had no control over his willpower and played against it, creating the monster inside of him today. So in my eyes, because of Jordan going through the Hells of Ryut and back and actually overcoming fear itself makes him one the most greatest Lantern that has EVER lived, alongside Abin Sur, who also had some long-overdued sins that had to be taken care of, as well.

Definitely Kyle

Hal.

My list is:

1. Alan Scott

2. Abin Sur

3. John Stewart

4. Kilowog

5. Sinestro

6. Hal Jordan

7. Tomar Re

8. Alpha lanterns

9. Kyle Rayner

10. Mogo

11. Guy Gardner

12. Sodam Yat