I've had my Pulsar 2 for almost 6 years now, and I've had very little use out of it thanks to some very bad hardware choices when I last rebuilt my machine

I've been plagued with errors on my current system which has the Gigabytedual p-III 500Mhz motherboard. The errors result in BSOD on Win2Kmentioning scope.sys and happen if I use USB at the same time the Pulsar2 I own.
However, it's finally time to upgrade my studio machine, and
this time I'm gonna ask for recommendations before buying

I have one Pulsar 2.
I'm looking to get one of these:
http://www.9xmedia.com/X-Top/X-Top---3across.html
What motherboard would you people recommend?
What processor?
What hard disk(s)?
(I intend to buy some USB hard disk to use for quick and easy offsite
backup

What graphics card?
(although I suspect 9Xmedia will help with that)
What memory and how much of it?
Anything else I should remember?
I'm not looking for the absolute cutting edge, but budget isn't too much of a problem...
Also, what software should I be using nowdays and where is the best discussion forum to participate in the community? The yahoo group seems to have died down a lot and won't currently send me mail...
cheers,
Chris