New 2xP4 Xeon system components...help!

I am new to the process of building a computer system and I have been asked to oversee the development of a workstation capable of handling CAD programs(AUTO CAD, PRO-E, Solid Works...) and 3D modeling, CFD (Computational Fluid Dynamics) software (i.e. KIVA), and also be able to produce DVD's from edited material via a capture card from analog and DV sources. Essentially I need an engineering platform and a digital editing system both with power. I have listed some preliminary selections for hardware below. I would be very happy to hear input from anyone on the subject i.e. what to watchout for, what works best, or what component may not work with the others. Information on Chipsets, Best memory configs and type (i.e. dual access), RAID selection, hard drives, types of card slots etc. would all be very helpful! I get lost when it comes to matching bus speeds to memory and hard drives....

Motherboards - Supermicro Super X5DA8, Tyan Thunder i7505 UANF, MSI E7505 Master-LS2

Chipset - 7505 (seems the best suited for my needs)
RAID (thinking of using 0 but open to suggestions)

Hard Drives - Three or four IBM SCSI 40 to 80 gig.(Do I want buffering? What should I look for to increase read/write speeds?)

Video Capture Card - Pinnacle or Matrox seem to be the most talked about, but which one would offer better capture rates and work with this system?

I really could use what ever advice the experts can offer...thanks!!

Sterling.