an intel board based on the 865, 875, 915, or 925 chipsets with a fast cpu and ddr400 is a safe bet. for a p4 system, get a processor faster than 3.2 ghz and you will realize good performance gains.
for the amd alternative, i recommend the msi k8n neo2 board, at least 1 gb of ddr400, and an athlon 64 running at 3200+ specs or better.