The i7 and 16GB of RAM are not needed for a gaming system - I'd say drop that and use the difference to upgrade your PSU to a 750W and whatever else you need (card reader, OS license, etc). Otherwise that all looks pretty good to me.
H77 is the basic, mainstream mobo. Z77 offers you the option of overclocking, and is for enthusiasts and overclockers. I would get Z77 since it's not too much more, and it is in general, better enginereed/built.