1) What kind of DVD are you using in the camera?
If you are using a DVD-R disc you need to finalize it before you can use it anywhere.
If you are using a DVD-RW you can use it only in DVD players (and computer DVD drives) that recognize -RW discs... plus they need to be finalized, too...
Check page 61 of your manual regarding finalizing...
2) You *might* be missing a codec... I recently needed to get a new video codec for an HP (Compaq) nc6220 laptop running XP and found that installing this http://www.xpcodecpack.com/ fixed the video-clip playback issue I was having... I don't know if it will resolve your specific issue and anything you download form the internet is done so at your own risk... but it worked for me.
I purchased a Canon DC100 Camcorder but unable to play the DVD on the computer. I am running XP Home SP2 and my InterVideo WINDVD Player won't play it. It works on the DVD Player but just cannot play it on the computer. I have a HP Pavilion a1200a. The sole reason I purchased this particular Camcorder WAS to be able to play it in both. I can play other DVD's on the computer but just not this DVD from the Camcorder.
Can someone help please or has a suggestion on what I can do to get it to play on the puter.