Hi,
I had faced the same problem before, for making a particular row the first in a datagrid, regardless of the actual position. Since I did not find any 'graceful' solution, I did this:
add a new column in the datatable, set ascending values to the rows for that column, set the sort of the datagrid to that column, and set the value of the row required to the least value. The column is hidden of course.