5. YES!!! Please ground yourself to a large metal object that has direct contact to the floor my touching it when building your own pc. This can stop static electricity from your body to fry all of your nice components! Also if you change something spec wise, Make sure that it still has compatibility
1. If you are going over budget with your ATX mobo, then also consider changing to a MATX mobo. This will shave some dollars and will also give you the possibility to buy a smaller case
P.S sorry i didn't write them all together