I'm going to be blunt about this, right up front.
I'm a die-hard Macintosh fanatic. Given a choice, I'll choose a Mac, even an outdated pre-OS X Mac, over any version of Windows ever. And for most users, I'll choose any Mac over any other Unix flavor.
I'm not going to talk about that today. Today I'm going to talk about non-platform specific digital needs for Campus life. Go with the OS and hardware manufacturer of your choice.
Most campuses now strongly urge all incoming freshmen to bring a computer with them. I agree, whole-heartedly. You do need your very own computer; yes, I know, there are labs on campus, but honestly there are times—frequently where you wait an hour or more to get to a lab computer, and then your time is strictly limited to, well, an hour or so. So even an outdated computer, as long as you can still connect it to the campus network (yes, that is crucial; either Ethernet or WiFi are required), is going to improve your life, and, more importantly, your chances of success.
People always ask; laptop or desktop? A desktop is, in some ways, cheaper, but it does in fact very much tie you to your dorm or wherever you're living. And honestly, that's thoroughly annoying; there will be times you'll need to research, and write, in the library. More and more students are taking notes in class on a laptop. Plus, if you have roommates, and you likely will, it's just nice to be able to take the laptop and your notes, or textbook, and go to a coffee shop or a bar and work. You've got food there, and it's warm, and it's community enough that you don't feel isolated— but you're not going to be socializing either. Plus, other people will be writing, and studying, too.
So. Get a laptop with WiFi if you possibly can.
The next thing you need to think about is backup. You need to be able to have two sorts of backup—emergency "OMG my computer had a seizure and I lost everything," backup, because, frankly, you might get away with that as an excuse and explanation, once, but mostly, you won't. You still will have to have that paper. So you need to backup up your files religiously, every week, at least.
That means you need to get either a small portable external drive; and yeah, you're looking at at least 100.00 for that, or you need to be absolutely religious about making backups using DVDs. So that means you'll need to get a computer with a DVD burner (mostly computers made in the last two years have drives that are just too large to backup to CD-ROMs.
In addition, you absolutely positively must get at least one (two is better) USB Keychain drives (sometimes called a Thumb drive, or a Flash drive), and keep one with you, with the stuff you've written in the last couple of days on it, all the time. You can get a two Gigabyte USB flash drive for $10.00 or less at any number of places. Get two, of at least two gigabytes (you can probably get 4 gigabytes for not much more money). One to keep on you, for portable backup, and one at home, because you will lose the first one. Shop for flash drives at Amazon, or Staples, or Office Depot, if you're comfortable shopping at Fryes, otherwise known as Geek Heaven; these retailers do really do tend to have great deals.
Printing; yeah, you can print at Kinkos, or Staples, or at the campus computer labs; but you can't do it ten minutes before your paper is due, and let's face it, an awful lot of us do need to print the final copy ten minutes before class. If you possibly can, just buy a small black and white laser printer. It's worth the extra money up front for the laser printer because even though the "Ink Jet" printers are less, the cartridges are going to end up costing more than the laser printer and a single cartridge. Keep in mind that most laser printer cartridges will happily print a case of paper, before running out, while the average ink jet, honestly, might get through two reams of paper.

