Help me pick my first Apple iMac.

Hello, this is my first post. I have never owned or even used an Apple computer before. I think an iMac would be about right for me but I need help.

Which of these 2 is the better one? ..........
1. previous generation.... 24" , 2.8ghz core 2 duo.
2. or the current model 24" @ $1499.

My local Apple dealer wrote me up a quote on the
previous generation iMac , 24" , 2.8ghz core 2 duo. $1249 as well as 2 2gb 800mhz ddr2 so dimm $100

So the previous generation with 4gb of memory for $1349.

Please give me your thoughts , which one is the better computer and why?
I want this to be a good experience
thanks

I suspect that the only significant different is the video card - NVIDEA on the latest model, but I doubt whether the difference between the two machines is going to make much difference. There may be some marginal difference when viewing films. However, if the deal is only $100 cheaper, why bother? If you'd beaten him down to $350 or $500, I could understand the importance of the question. But - $100? Go with the new one would be my bet.