Ok So I Have iAtkos S3 v2 10.6.3 with qoopz kernal 10.3.0 running perfect (almost) on my Dell Optiplex GX520, Which has A 3.4Ghz P4,2GB Ram,ect.

So I Have 2 Problems:

Need Help Updating To 10.6.6 Because i want Mac App Store (duh!)
Also I Need Help With Getting A Video Card with full working support (full res, Quartz GL/Extreme ect...The 2 Card I Can Choose From are:

PNY nVidia Geforce 6200 256mb PCI
BFG nVidia Geforce 8400 GS 512mb PCI

Please Help And Thanks!


EDIT:
For Some Reason When I Use GraphicsEnabler, it makes the 8400 GS Work Great but when i play minecraft it crashes the card and glitches up... Also I Am Wanting to use this machine to play minecraft and use iMovie '11...

I Have Had luck with the 6200 thought leopard but the 8400 GS and Snow Leopard are new to me.. So Please any help would be great!

Which Card would be easier and work better?