ATI 9700 is the gfx card to get, it kicks the GeForce4's ***. The problem with ATI was always drivers and now they seem to be getting that sorted, nVidia are just ripping people off at the moment.
I have a Gf3 Ti500 running a CRT (with P4 1.8a @ 2.47/RDRAM) and a Ti4200 running a TFT (with 2.53 P4/DDR) so I'm not exactly bias either... the Ti500 needed cooling mods and DVI modification which is unacceptible for a card that cost £350.
The DVI mod was especially necessary for use in Photoshop and other high detail 2D environments.
A fast P4 - a Northwood B I'd suggest - with a i850e chippy and some PC1066 RDRAM should do nicely.
Get a soundcard rather than using onboard as that's a) rubbish; and b) takes a bit of power from the cpu. Try to run it through a stereo rather than using PC speakers as they suck badly, 200W subwooferage is a must really
Regarding Dell, Gateway etc... they use oem gear with generic motherboards. For longevity you need a brand board where bios updates are available as well as full bios settings and full chipset functionality (memory timings, fsb frequency etc etc) these are not accessible on most pre-built PC's.
Javaman, Fluroinert costs ~$500 for half a litre