AMD can be less $$$ and still powerful enough. But, right now Intel has for sheer power. (I'm still using AMD though)
Not sure about current mobo. The last one I bought was a BioStar - and I love it! It has jumpers to push every limit you can think of, and it was not expensive ($100 or so).
My last computer was built over a year and a half ago - so it's time again.
Video card wise - ATI and Nvidia are pretty close - except that ATI's drivers are MUCH better right now.
My last 2 windoze computers have been great! Both running XP.
As for prices - newegg is good, but check pricewatch.com for the best deals.
Good luck....
