I currently use 2 crt monitors with a video card that has 2 analog ports. I will be buying a new computer and 2 LCD monitors. A lot of the video cards I am looking at have 1 analog and 1 dvi output.
Is there a reduction in quality if I use a converter for one of the monitors?
No, the monitors are expecting analog. Some of the older DVI-dsub converters had problems and actually caused a degradation in the signal, but if you're suing the DVI adapter that came with the video card you should be fine.