Which system do you think would suit me better (for a build)?

Slow down, slow down. Your forgetting the graphics card! It looks like your have quite a bit of money to spend, so maybe get a new sli motherboard, Asus is the best value and they always do have high ram capabilities so perhaps get 4gb of ram and then maybe get amd's athon 64 x2. For the graphics card get a nvidia and then maybe another later if you get a sli.