Security guru Bruce Schneier lays it out for you in essentially untechnical language.

Short answer: Microsoft has sold you out in favor of kissing up to the entertainment conglomerates, so consequently Vista is always trying to figure out if it needs to stop you from doing something unauthorized with copyrighted material. Always. We think we know enough about software in general and Microsoft in particular to realize that this will NOT end well for anyone concerned.

Options? If Windows is a must, stay on XP. If you’re buying new, consider switching to OS X or, if you can, Linux (geeks only, really). Vista is a non-starter; at the end of the day, if you pony up several hundred to several thousand for a computer AND a few more bills for an operating system, the resulting system should be unequivocally and absolutely YOURS, and should take orders from nobody else. We don’t think that’s an extreme position, but apparently Redmond does.