I own an iMac, which I run paralell with Windows. I allocated much less hard drive space to the Windows side, and saved the mac side for memory intensive functions such as video and graphics programs. I like the Windows side, mostly because I am a veteran user of CorelDraw, which only works with Windows, along with my preference for the Windows versions of Microsoft Word, among other things. I use the mac side for Adobe CS3, which requires a tad more memory than Corel products. This combination has worked out well for me, as I do freelance advertising design and photoshopping for clients in my free time, now that I am retired. I prefer Corel for design and layout, Mac for artwork and photography. I also use the Mac side to print glicees of my watercolors, because I like the precise nature of Illustrator for this purpose.
One thing I have noticed is that the Mac side of this machine is extremely stable, with virtually no problems normally associated with Windows computers. I would install Windows XP professional rather than Vista. If you can get a Mac through school, get it! Education discounts are available through Apple for any of their line, so take advantage of it while you can. You won't regret it.