Stopping production of the PS2 would be a bad idea because of PS3's production problems. Sony has trouble making the PS3 so without the PS2 they would have very few consoles to sell. Also they make a good profit off each ps2 and it is a lot cheaper for those who don't have much cash to spend.

And what point is that, exactly?  Perhaps you mean this one:  "The PS3 is extremely different. It's going to take a year to drop price to $299, so they need all the help they can get."

Oh, you mean help like having another system on the market competing with one of Sony's rivals' machines that the PS3 doesn't compete with effectively? 

The PS2 is part of what's helping keep away the perception that the Wii, 360, and PS3 are all in the same fight.  Instead, the Wii is half-in, half-out of a war with the last generation (the PS2) and to be sure the Wii is handily winning.  But on the other hand Sony gets to lose all the way to the bank which helps fund the war it has a chance of winning (and is) -- the one against the 360.  You honestly think Sony is eager to help consumers see the PS3 as "that system that's losing a little less badly to the Wii" and lose a major source of income at the same time? 

You may think otherwise but the fact is that most people who would buy a $130 game system are more likely to have been considering that purchase against a Wii or 360 and not a PS3.  If they were huge Sony fans they'd have bought it long ago, and if they're not they would be AT LEAST equally likely to buy one of the two systems within TWICE that price than one even more expensive.  So in fact discontinuing the PS2 is much more likely to help Sony's competitors more than it does Sony, even aside from the loss of its profitable system. 

Moving on:  I'll be honest and admit something -- I don't think the above quote is a complete example of your "point".  Rather, based on earlier posts, I think your point is something like this:  'The PS2 is from the previous gen.  Sony already won the war against the GC and Xbox, so the purpose of the PS2 is over now that it doesn't any more games I care about coming down the pipe.  If only Sony would kill it off already it could focus its efforts on the PS3 and win this war.'  (Note:  this is not supposed to be a quote but a summation of what I perceive to be your position.  See end of post.)

However, that is a fanboy perspective.  And I do not mean that to be offensive but as a diagnosis of the thought process that would produce that reasoning.  The "war" is not something that determines the actions of these companies except insofar as it affects who is most popular and therefore gets to sell the most product.  Selling product at a profit is what companies do, and when they are not selling at a profit it's because they think doing otherwise will let them get MORE profit in some other way.

So as long as selling PS2 systems is profitable for Sony, Sony will sell PS2 systems; and as long as Sony can profit from letting people publish and sell games for the PS2, and as long as people feel they can profit by publishing and selling games on the PS2, games will be published and sold for the PS2 -- unless, that is, Sony feels that such activity will cause them to lose even MORE profit than they would be making from the PS2 on another part of their business.  You seem to be convinced that the continued existence of the PS2 as a market force is an albatross around Sony's neck of such magnitude it outweighs the buoyant effect of PS2 profits on Sony's bottom line against PS3 losses and/or lack of significant profit. 

(This isn't like a "war" in that campaigns, however successful, cost massive resources to continue to pursue.  Instead, successful campaigns are a major source of income, which is what the PS2 has been for many years and continues to be.) 

I have explained above, in some detail, why I believe the PS2 is not significantly hurting the PS3 or, if it is, why it is hurting the PS3's competitors even more and therefore still not a drag on Sony's ability to compete.  Please explain, in detail, why I am wrong and you are right. 

Or, if I am completely wrong in my analysis of your position, please explain, in detail, it and "the point". 

why they should kill the ps2 they made lot of money from it

Sony should kill the PS2? Let's imagine for a second how this would play out...

SONY SECURITY: "Gah! A dump truck filled with money is COMING RIGHT FOR US!!!"
SONY EXEC: "Send it away! Quick! SEND IT AWAY!!"

A little dose of perspective.

I think Sony should bring Ps2 games to Playstation Network.
But the problem is are you gonna play Nhl 2009 for ps2 or Nhl 2009 for ps3 if you cleary see the difference.