the setting would be under Control Panel/default programs/set your default
programs
click media player amd at the bottom it should then say chose defaults etc
on that page you can check which types of files you wish Media Player to
play
peter

control panel--folder options.

With Players like Quick and Media I think there is a Default Selection
in  " Set Program Access and Defaults".   For any file just rt click and
select Properties>Opens With - Change. Found at upper portion of the dialog
box.

The simplest solution would be to configure this within Windows
Media Player.
At the top of the Media Player window, click on Tools.
Select Options from the drop down menu.
In Options, click on the File type tab.
Check the file types you want opened with Media Player.
Click OK.

Another approach would be to right click the song and move your
mouse pointer to "Open with".
Select "Choose program" from the menu.
In the Open with dialog, select Windows Media Player.
Put a check mark in the box next to "Always use the selected
program to open this type of file".
Click OK.

You can also make Window Media Player your media player through
Control Panel -> Add or Remove Programs -> Set Program Access
and Defaults (in the bar on the left side) -> Custom.

Good luck

Nepatsfan