It depends. If the card is PCIe, you're in luck; if it's AGP, then you're out of luck. Honestly, though, it’s a pretty weak card for gaming. You should probably double-check the minimum requirements for FIFA 10 and Football Manager just to be safe.
Look for a used NVIDIA GeForce if you actually want to play anything.
The best you'll likely find for an AGP slot is an HD3850..
It’s not worth sinking money into a high-end card right now. You really need to grab at least another 512mb of RAM first.. it'll make the whole system run better.
AGP and PCIe are, though. For $233, you're better off just grabbing a new CPU, motherboard, and RAM, then selling this old rig. The motherboard will have integrated graphics, which is fine enough for basic 2D games, but honestly, there's just no point in sinking more money into that machine.