by Eric GriffithDid you receive a pristine, mint Windows 7 (or even Vista) computer this holiday season? Great, but right out of the box, every computer is far from perfect. Unlike most electronic devices, which you can plug in and use instantly, PCs—particularly those with Windows—need some adjustment before they're ready for everyday use. You need to make your new system safe, and also personalize it with your own preferences. There are programs on the hard drive you should get rid of, and other things you should add immediately. If you haven't yet been introduced to Windows 7, or it's been a while since you've set up a new machine, we'll walk you through it all in these 12 simple steps. If your new baby is a Mac, you've got a much shorter to-do list.After you've devised clever ways to...