Watching DVDs on the PC is much easier and cheaper than the TV out version.
My TV has only about a 15 inch screen so it's smaller than most monitors. If I had a nice 21 inch monitor like I do at work I'd probably have settled on this for a time.
Basically, if you have a working card and install the WinDVD software you should be ok.
You may need to make a few optimization changes.
You may want to make some changes to the WinDVD settings using DVDGenie.
Maybe hook up the line-out of the soundcard to your stereo...
Have fun!
Other choices:
What you need to watch DVDs on a TV if you don't want use a decoder card.
What you need if you want to watch DVDs with a decoder card.
What you need if you want to make a copy of a DVD to a video tape. (This is not illegal for private use in Germany, see the law here).
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