I have a SSRS 2005 report that shows prices of things. For some customers, I hide a column from the table (with an expression on the Visibility - hidden
The best choice is to duplicate the table and put in above the other with the columns you want to show. Then you can set the visibility of the table dinamycallly. In order to make them editable you put one table a little smaller thant the other to select it when it is above one.