Whatever you do DO NOT install it online if you do install it. Get a CD copy of it and install it that way. If something happens to drop your net connection or interrupt the install it can lock you out of your PC such that you have to reinstall Windows to recover. I've had it happen to a number of clients and it's cost them a good penny. My recommendation is to hold off yet on SP2 - there still seems to be a few bugs in it.