If the iMac has an Intel processor, it probably comes with Boot Camp. Boot Camp will let you boot into Windows. You'll need to own a copy of Windows and Windows XP would probably be the best. (I'd certainly stay away from Vista.)
If you get Fusion or Parallels, you can use them to have Windows running at the same time as the Mac OS. I've been using Fusion and EQ6 with no problems. Software vendors will generally say they don't support it, but it works very well for everything I've tried.
There's a forum for Mac EQ6 users on Yahoo groups.
Hope this helps!
--Heidi
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