Here is a javascript that detects Windows Media Player and its version.
*OBJECT classid=CLSID:22d6f312-b0f6-11d0-94ab-0080c74c7e95
codeBase=#Version=6,4,5,715 height=1 id=WMP64 width=1|*/OBJECT|
*OBJECT classid=CLSID:6BF52A52-394A-11d3-B153-00C04F79FAA6
codeBase=#Version=7,0,0,1954 height=1 id=WMP7 width=1|*/OBJECT|
*SCRIPT language=VBScript|
*!--
On Error Resume Next
WB_DWM52 = (IsObject(CreateObject("MediaPlayer.MediaPlayer.1")))
WB_DWM64 = (WMP64.filename = "")
WB_DWM79 = WMP7.versionInfo
//--|
*/SCRIPT|
*SCRIPT language=JavaScript|
*!--
var WB_WM="undefined";
if( WB_DWM79 ) {WB_WM=WB_DWM79.slice(0,3);}
else if( WB_DWM64 ) {WB_WM="6.4";}
else if( WB_DWM52 ) {WB_WM="5.2";}
else {WB_WM="undefined";}
document.write("Windows Media Player:" + WB_WM);
//--|
*/SCRIPT|