on board graphics or add on

1. No: If you do not wish to game you do not need another card.
2. 630i is the nVidia chipset on the motherboard: you could consider a chipset to be a sort of traffic cop for information, which ties everything together.
3. 630 is the model, and i means integrated. The model number is relatively arbitrary, and does not hold any particular special meaning. Sometimes a bigger number means a newer model with more bells and whistles, but often times a larger number means absolutely nothing.

You are never too old to game. Try Civilization-2. It will run nicely with integrated graphics.

+1 geofelt, never too old, I was older than you when I started, the only real drawback is that you continually upgrade your setup regardless of how many times you tell your "mature" self you won't do it.

Hey, it took me FOREVER to figure out what it meant, so don't sweat it.