Newbie to RTW

I bought RTW, while I still enjoyed MTW. Due to a graphics card upgrade (GF 6600GT) I can no longer play MTW.

I have now loaded RTW, and the patch and started playing. While it is different to MTW, I will still enjoy playing it. It is similar enough to MTW for me not to be troubled by any new features.

I can not set up my display to 1280x1024, my native resolution for my 19" LCD. I am forced to use a lesser resolution, and in order to not make the text look blurred, I have turned off scaling to size. I looked briefly at quietus guide, considering my card Leadtek Geforce 6600 GT 128MB can I set

Vertex Shader Version = 2
Processor Speed (ghz) = 4(2.5 Ghz) (I have a Athlon XP 1800)
Physical RAM (MB) = 4(512) (I have 512 MB)
Video RAM (MB) = 3(256), even though I have only 128MB, but the card is very fast.

I could possible select 1280x1024x16 instead of 1280x1024x32