No problem man, you need the Nic card to connect to your ADSL modem. Be good if you could find the one that came with the package.
Are you going to use the extra space? if so then get the 60gb, in my opinion if you have a CD Writer then you don't need it (i am an avid backerupper).
Hard drive technology is changing shortly with the mainstream introduction of Serial ATA. Some Serial ATA drives are around at the moment, but not many. Worth it for graphics/video editing but not much else.
I'd save myself $50 and get the modem if I needed it.

SimJen