Can't Play DVDs
Rommel asked the Answer Line forum why DVD movies won't play on his XP PC.
Unless you have the Media Center edition, Windows XP can't natively play DVDs. You need either a third-party media player that can play them, or the right codec. Fortunately, you can have your choice of either of these options for free.
Vista, on the other hand, can play DVDs right out of the box. And that includes the Business edition, which doesn't have Media Center.
And no, updating XP's Media Player in to version 11 won't let it read DVDs.
If you're partial to Windows Media Player, download and install the XP Codec Pack. Once installed, you can insert a DVD, select Play DVD Video using Windows Media Player, and get a movie instead of an error message.
Or if you prefer another player, check out the free VLC Media Player.
My thanks to the folks at forum, especially crazy4laptops and Flashorn, for their contributions to this answer. You'll find the original thread at http://forums.pcworld.com/message/222369.