powerbook g4, it'll be beefier for the apps you're going to want to run. The ibook is the playtoy version of the lappys. Both will be good but if you have a choice, go powerbook.
Also, to do the wireless thing you have to make sure your laptop has an airport card(wireless network adapter) which most of the g4 mac laptops came with. If you have wideband access at your home/dorm, all you'd need is a wireless router to go with your wireless network card. If you need help with any of that stuff, drop a pm to me or some of the other guys who will post in here like anthony or something, we know our crap.
T.c.