it seems you have an onboard graphics card. what i would do is check if it's AGP or PCI slot. (crack open the case)

after that, you'd just go pick up a $40 dollar card and it should work fine. assuming you don't do any major gaming.

mushroom's right on about the ram. however, again with the gaming, i recommend just picking up another 512 because 1gb is enough for basic needs.

compare your slots to this image:



usually if you have an AGP slot, you'd only have 1 or 2. it will be outnumbered by PCI slots.

both of these components are plug and play. video card will just require drivers.