If running a 64bit system, most likely #2. If 32bit (x86) #3. Do the downloads one at a time (especially the Windows SP1). Then do any further system updates in groups, say of 3, 4 or 5. Just pick a convenient number to split the total by. As has been said, some updates will depend on others already being installed, if they fail, think of a line of dominoes toppling.