What would make a good computer for playing Minecraft types of games

This is what i have:

Intel celeron dual core 1.8ghz (might overclock)
NVIDIA gt 520 1gb graphics card
4gb of most likely 800mhz ram
and a Foxconn H61MD LGA 1155

This computer is going to be for my brother because he doesn't have a computer and this is what i was thinking about because he would be playing internet games, minecraft, and robocraft. thanks for reading this.

if you need the links to the item email me at Tunjikusimo@gmail.com