I suggest you to modify the ToolbarMode property of RadEditor for MOSS. You can find an online demo of the matter on the following address http://demos.telerik.com/aspnet/Editor/Examples/ToolbarMode/DefaultCS.aspx
In order to set the ToolbarMode property you need to modify the respective ConfigFile.xml located in the /Program Files/Common Files/Microsoft Shared/web server extensions/wpresources/RadEditorSharePoint/126.96.36.199__1f131a624888eeed/RadControls/Editor/ folder.
For example add the following line:
I hope this helps.
the Telerik team