first,you should list the features you need.
for example need network or not,need a special video(VGA) or sound card or not.
if you need network you can buy a lan onboard mainboard.if you don't need a special video(VGA) or sound card you can buy them onboard.
ASUS motherboards are good choices because they are cheap with good features.GIGA motherboards are good too,with a lot of different models.foxconn is a new motherboard with good features.
then you should check if you want ddr2 rams and sata hard drives for better speed.your mainboard should support ddr2 and sata.it's better if you have more "ram and pci" slots.you should check if you need intel or AMD CPUs.your motherboard should support it.
I think the best chioce for not a special user is a motherboard with these features :
AMD support upgradable to higher CPU speed,DDR2 RAM with 3 and above slots,SATA HARD drive,
PCI and PCI-E slots,LAN and sound onboard (not VGA)
why don't you pick my answer as the best?????