Office. It simply isn't worth the risk in college to run into any problems. Also, many colleges have deals in place with Microsoft to get office for cheap. I got Office 2008, Windows Vista Ultimate, and Office 2004 for $7 each.
I agree and would encourage you to check into this
You should be able to get either Office for the Mac or PC at a reduced rate
In general...
If you need strict compatibility with MS Office for Windows, your best bet is to run Windows and MS Office 2003 or 2007 with Boot Camp or virtualized with
Fusion/
Parallels/
Virtual Box (free)/
Crossover.
If you need mild compatibility with MS Office for Windows, you can use Office 2004 or 2008 for the Mac, with the understanding they are not equivalents and there is little VBA support in 2004 and virtually none in 2008. Excel will be the primary difference more so than Word. That probably won't make a difference for you in college, but will in business.
If you want MS Office-like interface, etc. then
Open Office/
Neo Office are good choices and they are free. But they will not provide strict compatibility with MS Office. They will however, give you a more Office-like experience.
If you want the functionality of MS Office with a Mac experience, the iWork is the best bet. It is a great value for the cost. Pages is a great tool, and Keynote is superior to Powerpoint in my opinion. Numbers is good, but does not provide the power of Excel. You can check out a comparison here:
MR Guide - iWork v. MS Office. You can export and import Office docs, but there are issues at times.
You can also check out
Mariner Write and Mariner Calc
If you just looking for a nice word processing, then
Bean is free.
Woof, Woof - Dawg