after uninstaling wmp 11 should I also unistal windows media format 11 runtime

any help would be great thanks Ray

Its not a good idea to remove the runtime components. If you do that then Windows Media files encoded in WMF 11 will not play properly.

i also thought that it would be unwise to uninstall the runtime....but this article nade me think different :-

How to Uninstall and Rollback Windows Media Player 11

Rolling back to a previous version of Windows Media Player 11 is a feature of the Windows operating system and cannot be removed entirely. What the hell was Microsoft thinking not letting people uninstall windows media player 11. Windows media player 10 seemed ok. I ever like WMP9 too.

However, in Windows XP, you can roll back to the version of the Player that was previously on your computer. Let’s see how I found the easiest way to do that…

You must be logged on as an administrator or a member of the Administrators group to perform the following procedure. Please don’t try this under Windows Vista Beta. It fried me and the computer. haha. Although by now a lot of you already are running the new Windows Vista home or office or whatever they call them now.

1. Disconnect any portable music or video devices that might be attached to your computer. For more information, see Issues with devices after removing Windows Media Player.
2. In Category View of Control Panel, click Add or Remove Programs, and then click Remove a program.
3. At the top of the list, select the Show updates check box.
4. In the Windows XP - Software Updates section, click Windows Media Player 11, and then click Change/Remove.
5. In each of the two confirmation dialog boxes that appear, click OK.
6. When the rollback process is complete (it might take several minutes to complete), click Restart.
7. In Category View of Control Panel, click Add or Remove Programs, and then click Remove a program.
8. At the top of the list, select the Show updates check box.
9. In the Windows XP - Software Updates section, click Windows Media Format 11 Runtime, and then click Change/Remove. If you installed a non-US English version of Windows Media Player 11, the instructions in the dialog boxes that are mentioned in steps 9, 10, and 11 might appear in English.
10. In the first confirmation dialog box that appears, click OK.
11. In the second confirmation dialog box that appears, select the Do you want to continue with the rollback? check box, and then click OK.
12. When the rollback process is complete (it might take several minutes to complete), click Restart.
13. In Category View of Control Panel, click Add or Remove Programs, and then click Remove a program.
14. Click Microsoft User-Mode Driver Frameworks Feature Pack 1.0, and then click Remove.
15. Follow the instructions that appear in the Software Update Removal Wizard. If the Wudf01000 confirmation dialog box appears, click Yes to continue. When the software removal process is complete (it might take several minutes to complete), click Finish.

If you remove Windows Media Player 11 and the Windows Media Format 11 Runtime, and then encounter error C00D271D (”A problem has occurred in the Digital Rights Management component. Contact Microsoft product support.”), you might be able to resolve the problem by installing the Windows Media Format 9.5 Runtime. For information about installing the Runtime, in the Microsoft Knowledge Base, see article 891122, “Update for Windows Media Digital Rights Management-enabled players.”
You might not be able to roll back to a previous version of the Player if the hidden folder $NtUninstallwmp11$ is deleted from your computer. Some non-Microsoft programs (such as CCleaner) delete this folder in an attempt to remove unwanted files from your computer.

http://www.kensavage.com/index.php/archives/how-to-uninstall-and-rollback-windows-media-player-11/