This CPU you linked me,has no Hyperthreading
as i told above,it's a big disadvantage
Since you can get a PC with Hyperthread(which is important) ,especially an i7 with your budget,why not doing it?
but i don't say what this cpu isn't good,it's perfect for now
about case,i agree with Intrepid
About SSD,don't do it now,you will be able to buy one soon really cheap!