The 7NJS is a very nice board - top performance and tweakability, and loaded with features. However you do have to pay for all that with a lighter wallet. Some more info on the 7NJS can be found
here.
I'd also recommend the Asus A7N8X again a great feature set and performance, with the resulting pricetag, or the EPoX 8RDA+ if you're looking for the best price/performance mix. A word of caution with the 8RDA+ though, they put the memory slots too close to the line the video cards take, so if you're using a video card such as Ti4600, or with a similar large PCB you'd have to bend the card slightly during installation to avoid a transistor being knocked off.
The XP2600+ will make for a great CPU, the ones being produced now come with a 333Mhz DDR FSB by default, allowing it to make more effective use of the available memory bandwidth. Below that, and you go back to the 266FSB, above that and the prices jump substantually to the XP2700+ and XP2800+.