If ever you want dirt on GPUs, read Tom's Hardware Guide.
The 9200 isn't worth bothering with. The Ti4200 is a great little card - and there were AGPx8 versions - but it's missing shaders necessary for new stuff. The lowest you should be looking at for reasonable performance is a 9600, preferably a 9800. If you just want Tigercandy but no games, an NVidia 5200 will be fine.
Edit.. yes, I realise THG is PC-centric, but the relative performance when real numbers are set aside is still very relevant.