you might want to check out this place, really good
http://www.ncix.com
what about HD?
i would get 2 HD
WD raptor 74GB. partation the HD C: for your os and D: for all your programs you will want to install.
and the other drive can be your storage drive.
as for mother boards. sataII is alot faster. but i'm not sure what HD supports it as of now. heard the new raptor just came out.
but u should really check out
http://www.hardocp.com and read their forums there.
lots of good info.