In general you won't notice a significant difference from one step higher CPU in the same class except for a much lighter wallet. I would opt for the 2nd or 3rd from the top i7. The i7 is already going to be great for video and image rendering due to hyperthreading - I read that somewhere, not based on experience.
I always recommend the best GPU option available simply because you can't upgrade it (unless you're talking about the Intel HD 3000). You can easily upgrade your hard drives, memory, CPU, but not the GPU. It's better future proofing and doesn't cost that much more.
As for RAM, I went with 8GB with the option of upgrading later, but it has never been a bottleneck so that is probably just fine.
Last edited by kuksul08; 11-15-2012 at 01:09 PM.