Steam Download

Hey guys!

Still trying to debate on whether to get FM2009 (kinda hooked with PES 09 and FM08 seems to be satisfy my managerial needs), so I was wondering:

1) How large is the steam download? Can you resume downloads? I dont have the fastest connection in the world..

2) I know my old rig (P4 3ghz, 2 gig ram, ATI 128) wont be able to keep up with the new 3d engine and I hear there are variants of the 2d engine? What are these?

3) Is it really worth the upgrade?

Thanks guys