I love the G3258, particularly for a starter system.
Your build will work.
I have some suggestions:
1. Make that ram a 2 stick kit so you can run faster dusl channel operation.
2. A GT610 is not considered a gaming card. If budget is a problem, start with using integrated graphics until you can buy something stronger.
A GT730 at about $70 would be the minimum.
3. Can you manage a $30 cm hyper212 cooler? If not now, later. The big value of the G3258 is it's immense overclocking capability. The stock cooler will only go so far, and it gets noisy under load.
4.. Consider deferring on the hard drive in favor of a SSD.
I will never again build without a ssd for the "C" drive. It makes everything you do much quicker.
120gb is...