Actually Windows 2000 is up to Service Pack 2, and for me it helped a lot.
As for the dual Athlon thing, yes win2k will support that, but truth be known one Athlon 1.4 Ghz is at least the equal of the 1.8 Ghz P4. (The Athlon tends to win all Office, Mathematical, and Direct X gaming applications. The P4 wins in Quake 3, Flask MPEG 4, some "internet" benchmarks. They are fairly even in most others.) Two Athlons would just be murder (dual P4 does not exist yet). Currently there is only one dual Athlon board, and it's expensive. Fortunately Tyan is releasing a cheaper version that does not have the onboard Ultra Scsi controller.