Well that board should be ATX Form Factor and you just get a case that says it fits all standard ATX Form motherboards. Mind you don't get a micro-ATX standard as that's a smaller board setup obviously from the name
BTX is making its way into the market, meant for massive systems if im not mistaken one i saw had 12 bays mounted in front, and space for a really big mobo
You don't want a mini-atx case, you want an ATX Form factor case as that's what your motherboard is and even if it is mini or micro-atx you still might want to upgrade in the future. Get a mid-tower ATX Form Factor case.
Thats a good cpu. I recomend getting the Mid tower case plus a Thermaltake Volcan11 Xasier edition and OC the cpu to 2.3ghz. I did that in my old system and worked really good and was completely stable. Also before you do that make sure it is a Barton core.