Since the case supports both standard types of motherboards(form factor) - ATX and microATX and you have ATX mobo , everything is OK .just one more check :for usb front header - see it or use pcpartpicker . no problem .
I was concerned about hole spacing as it seemed weird
It just looks that way because the board is so narrow. It will fit fine.
You might want to pick up some of these http://www.amazon.com/StarTech-Plastic-Motherboard-Stan...
... to put in the small corner holes for a little extra support for inserting/removing RAM and the 24 pin connector. They help take the strain off the board. Asrock uses thin strata for their MBs.