hmm, i gather the nForce2 seems to be the mobo of choice for AMD setups now, especially for new builds & complete upgrades, as can get the less "important" (read: most important but least interesting 😛) stuff onboard, combined with excellent performance. Also seems most likely board that will be reasonably upgradeable. With reagrd to inidvidual brand, well all same chipset so not THAT much difference, but usually less risky to get some sort of decent brand, asus, epox, abit, gigabyte... TBH it's worth researching you mobo, more than any other peice of hardware. Even just looking for what chipset features you want, seeing what manuf'ers make it as you want then try to research the inidvidual boards, usually will be down to like 4 max at this point, where can make one of those "which mobo" threads 😛 or even just ask someone in a thread where someone happens to say they use a board your looking at.
A lot of ppl will rant either amd sux0r or intel sux0r blah, blah, mostly it comes down to amd = more bang for less buck, intel = most bang for mega buck 😉 More important difference imho (as a gamer) is the chipsets, which of course are only available to either one of amd or intel. Once you've decided on chipset/mobo, the rest is easy.
HDD: probs 60gb+, though always easy to adda second disk later if you need more space; either
Western Digital Special Edition (8mb buffer) for max performance
Seagate barracuda IV (for still great performance but silent)
- anyone seen review of those new Maxtors? 8mb buffer like the WD but fluid dynamic bearing things like the 'cuda... looks interesting but not seen review though 🙁
cpu: fast as you can get with the cash left over
ram: 512mb, Crucial for cost effective, Corsair for max performance/overclockability. Maybe few other suggestions.
soundcard: onboard probs fine, esp with an nForce2
PSU: 380w or 430w Antec Truepower for max quality, a 350-400w Enermax or other Antec be fine though to save costs.
gfx: lots of choice, radeon 9500pro, r9700, gf4ti4200, gf4600... depends on budget and if in ati, nvidia or dont care camp.