DVD--How to Play a Movie?

I have a Compaq Presario 5000 here. The computer came from Compaq equipped with a DVD player so I guess its hardware is capable of playing a movie. It belongs to a friend. Now, playing a movie on a computer seems to me to be about as useless as a steering wheel on a bicycle; but, she wants it to work and I said I would help.

First off, I know nothing about playing a movie on a DVD-equipped computer. When I insert a DVD movie, obviously, nothing happens and I have no idea how to make it work or what, if any, additional software I might need. Also, I have searched the Programs menu and find nothing there that will work.

Now, will someone take me by the hand and lead me through this?

 

In the quick search I did I could not find out what programs came on Compaq Presario 5000. I did find on the 6330 model it has InterVideo WinDVD to play a DVD movie. Another company that sells DVD player software is Cyberlink PowerDVD.

 

I found a copy of Power DVD here; but, the sound volume is so low I can barely get it up to comfortable listening in a quiet room. All other sounds are easily run up to much higher levels. But, I consider it fixed for now.

She can call Compaq to solve that problem.