If you're thinking about a new computer, keep your old computer and your old OS too. Then you can have Vista, XP and a Mac if ya wanna.
In my case, I'll have Vista, XP Media Center, Windows ME, Windows 2000 Pro, Windows 98SE and Windows 95. All still work, no conflicts running any software, because I can still run it on the machine it's already on.
No mac for me. My son bought a Mac laptop, the OS self-destructed, and will not reload off the disks. It fails the boot up before the disk becomes active. It's a Mac doorstop. Just sayin'.
Now I do also use a PC. cheaper to buy and upgrade. I like them both when they work