Video Editing Machine

[Itzmemark]

I will be doing some video editing from my go pro footage will I see the difference between dual core vs quad core? Also I have a 2tb external via Firewire 800 will it be fine to process through there of just have it on the physical HD? I already know from a previous post that I will need to max out my ram. What about the video card? I currently have a macbook pro with 128mb but go pro suggests 256 what is the difference between 128 and 256? I have seen that there is 512 and 1gb is there a big difference there? I know I am asking a lot but you fellas seem like you have much more knowledge than me when it comes to these things. Also if you have already responded to my iMac question I thank you, I'm just trying to see if I need the iMac or I can use a mbp. THANK YOU IN ADVANCE!!!