I don't know of any DVD drive with a built in decoder.
Most "retail" packaged drives come with a CD that has decoder software.
The last I checked, there was only 1 free DVD decoder, and it has very limited functions.
This is the Xing player.I was able to purchase WinDVD from www.newegg.com for $1.
It was listed as OEM software in the dent and scratched section.
I have also seen Power DVD and WinDVD for under $10 at numerous other sites.
The video card mfgs that do provide DVD decoders typically will not allow you to install an update unless you have the player from the CD installed.
One brand of video card that does come with a player is ATI.
If you have a generic video card, look over the driver CD closely. I found Power DVD on several muti-device driver CDs.
Chas