Mac OS Leopard (the current Mac OS) virtually has no viruses for it, and Mac OS X has the most advanced security system ever created in my opinion. Mac OS uses OpenGL, which basically has the same capabilities as Microsoft DirectX. Mac OS is also built on UNIX, which is to some the best operating system ever created. An iMac has no 'CPU box', but contains the entire computer behind a brilliant TFT screen. Since it is based on UNIX, Mac OS X Leopard is statistically more stable than Windows. Many think that Macs are more stable, aesthetic and pleasing than PCs and Windows. With a Mac you get some awesome bundled software called iLife, which contains software that lets you edit movies and photos, record and edit music, create a websites with a few clicks, and create your own DVDs with animated DVD Menus. Mac OS X Leopard features include CoverFlow, which gives you a brilliant visual of your document and application icons using OpenGL reflection tools and such. QuickLook in Leopard lets you view your documents,movies, and photos without opening the actual application! Leopard contains some of the most advanced features (system and user wise) and uses aesthetic views and effects. I would get a Mac if you like nice looking desktops, no more computer freezes, awesome built-in software and features, if you hate that trial software that comes with a PC, if you hate virus scanning and disk defragmenting, and if you like your computer to allow you at one minute to be very productive and the next minute to have fun with the built in iSight camera or making your own DVD. i am 95% positive that you will love a Mac.