...as comparisons for the old PCI range of graphics cards are few and far between now, however...
As a rough guide, the closest AGP versions to those two cards are AGP nV5600 and ATi9200 which are benchmarked and compared on Tom's Hardware :
The nV5600 is about equal with the Ati9600, which scores both much faster in 3D gaming than the much lower end 9250.
However the 9250 in the link you provided does apear have a DVI connector (if you need one), but as far as I could find the nVidia 5500's are the fastest PCI graphics cards remaining on the market.
for a PCI slot. ive been mainly looking around newegg and have narrowed it down to these 2 cards, but other suggestions are welcome.