2D Acceleration is pretty mature in both the ATI and NVidia drivers for 
XFree86. You have to note, however, though that the FPU on the GPU is 
not used in 2D acceleration. Instead, the 2D acceleration is mostly a 
function of the bus bandwidth (both from the CPU to the GPU and GPU to 
the GPU memory) and the RAMDAC draw speed. The interlacing problems 
you're seeing might be a offshoot of a cheap RAMDAC (although, with 
ASUS, I highly doubt that). The clock rate of the Ti4200 and the width 
of the connection for main system memory to the video memory is probably 
the most important of all.

I would check your BIOS to see if you have enabled the maximum clock 
speed for your RAM and also make sure AGP 4x is enabled and that Option 
"AGPMode" "4" is in your XF86Config. Look, also, for options to allow 
automatic RAM timing adjustment and other advanced features of your 
BIOS. Don't go too crazy, but play around with different settings.

The only feature not currently implemented in XFree86 2D is hardware 
alpha for arbitrary pixmaps. This is slated for XFree86 4.4. This 
operation uses the FPU quite a bit, so, plan to see your nice card pay 
off in that department.

> Out of curiosity, how does using the NVidia drivers for your GF2 chipset 
> compare with the nv driver (which I think supports that chipset)?  I'm 
> less interested in 3D performance than in 2D acceleration (ie standard 
> windowing stuff used when running word-processors & spreadsheets).

-- 
Jason Clinton
I don't believe in witty sigs.