sounds ok, but there are a few changes that would help.
I woudl get this
motherboard, or this one
because they are really really stable.
the graphics card should be the 9800Pro 128mb, because it performs better than the 256mb version in most circumstances, because ATi changed the architecture of 256mb.
if you are going to overclock, get good ram, you should go for Corsair or a good brand (OCZ, geil etc.) you will be ok with DDR333, even if you are clocking it to 200Mhz, Provided you dont get cheap, crappy ram
like regulus and willsko said, you would probably like to get a bigger harddrive, even if you arent going to use all the space, (you might use more than you think and then you always have room for unexpected stuff) also make sure the hard drive is SATA because it will increase system performance noticably