Well. If it was 33K6 speed, I estimate the time taken would haven been around (25 * (1024 ^ 3) / (33600 / 8) / 3600 hours. 
You might save yourself some money in the future with a special request to a friend who has highspeed internet available to send you the additional campaigns posted here on the forum created by some fans and AOE Forgotten Empires developers on DVD or CD-ROM using snail mail.