The price difference between RDRAM and DDR Sdram is really slim right now. If I were building a P4 system for myself, ( ha

) I'd go with RDRAM. (Even though Intel is planning on dropping Rambus by the end of the year.)
If you look at the benchmarks on Tom's site with their overclocked P4 you can see that the 2.6 Ghz P4 w/ Rambus (overclocked) beats out the 3 Ghz P4 with PC2100 DDR ram. The DDR ram based system actually seems to gain very little performance as the clockspeed goes beyond a certain level, this tells you that the memory (or something else specific to that system - i845D chipset itself? ) is holding the system back.
From a performance standpoint RDRAM is the way to go, but truthfully anything you pick is fine, as long as you don't go with the "old" i845 with PC133 SDRAM. I've heard good things about the Asus P4B266 as well. (i845D)
On the video card, GF4 Ti 4400 or Ti 4600 would be my picks. I don't really have a brand preference. I can't say that I've really had a problem with any brand I've tried, as for the most part they just copy the nVidia reference design anyway. (Asus has sometimes done their own thing for their VIVO cards, but those have been solid as well. I personally have owned one of these and was happy with it.)
As for my own opinions regarding AMD vs Intel, I'm pretty neutral right now. The 2.2Ghz P4 performs well vs the XP 2000+ (virtual deadlock). The AMD processor is still cheaper, but it's not as bad as it once was. "Hammer" may decisively swing the pendulum back to AMD, but it's too soon to tell right now. I understand that being an Intel employee you probably aren't considering AMD. (There may be hope for you yet though: One of our Electrical and Computer Engineering professors here at Oregon State University now has an Athlon system in his office, even though he is a former Intel engineer who worked on the P5 and possibly on the P6 cores...

)