Are you using a wireless or wired mighty mouse? The wireless mighty mouse only works with Mac OS X v10.4.6, whereas the wired mighty mouse works in Mac OS X, Windows 2000 and Windows XP.
The wired mighty mouse uses standard windows drivers already available in Windows so it should work.
Nah, it's a two button mouse. I know this because I was in the Apple store once and the salesperson didn't know how to use it. She right-clicked every link in the browser and wondered why it was bringing up a menu instead of opening the link. She ended up opening every link in a new window. I just watched and laughed.