Stop users changing the default style..
 

At the bottom of all forums there is an option to change the forum from the default style to another if the XML file and template styles have been uploaded.. eg. Black-Ice..

Is it possible to hide this option from members/users so your style you implement is the only style you see ?

Theres a check mark next to each style you install in the style manager. If its marked users can use it, if its unchecked they can't.

--------------- Added [DATE]1216858866[/DATE] at [TIME]1216858866[/TIME] ---------------

Also if your problem is that you can't uncheck it, its because you need to go to
AdminCP->Vbulletin Options->Vbulletin Options-> Style and Language Settings
and then set another skin as your default.

Set your default style in the AdminCP -> vBulletin Options -> Style and Language Settings

Then on the same page "Allow Users To Change Styles" set to No