I have a Geforce 2 MX 400 64 MB in my older computer, an EXCELLENT card for the age. Still plays JK2 and SFC3 perfectly, despite being used in tandem with a 900 mhz Celeron processor.
I would recommend getting a Geforce FX 5200 128 MB card, its the cheapest 128 MB card around ($99) and if you look you can find a $99 one from VTY that has dual-VGA for dual-monitors. Excellent card- I have one in my new computer.