Ricebook isn't quite right.
As far as programs, you will need the Mac OS X versions unless you plan to install Windows via Bootcamp. Drivers, though - a lot of those are pre-built into the OS. Depends on your scanner and tablet, though, and whether or not the companies that produce them support OS X.
For the most part, it's true: Macs aren't susceptible to viruses, et al. They're just not written for the OS. Basically, they don't work for the same reason a Windows program won't work: they don't speak the same language. If you're running Windows on your Mac, though, you'll still have to be careful and use an anti-virus program; the Windows part DOES speak the language.
I hope any of this has been a help.