Page scrolls to top when clicking a horizontal scrollbar and RadFormDecorator styles a select in IE9
For the time being the select can be skipped from decoration:
<telerik:RadFormDecorator runat="server" ID="rfd" DecoratedControls="All" ControlsToSkip="Select"/>
There is also a script attached that provides a workaround for this issue.
The problem manifests itself only in IE emulation and we consider it more or less a browser issue. The problem root is in the browser raising the mouseup event right after the mousedown event before the user has released the mouse button.
Please, check the attached workaround for ways for patch this if IE emulation is part of your scenario.