Any card from that era or a year or two forwards will work.
Your motherboard has a few PCI slots, atleast 1 or 2 unoccupied, and a single, probably currently unoccupied AGP slot.
I assume you are using Windows XP? If you are, you will probably have to download the drivers manually before everything looks nice.
If you are using Win Vista and onwards, they have generic drivers that will do just fine.
If you are using Linux, you will learn to loath and love xorg.conf