>Could someone please tell me a sinple way (non programming) how to insert a drop down list in an existing grid where a text box is now.

Once you edit the grid, click on the specific column. You should have the editbox entry to be refreshed in the property sheet. Click on delete to remove it. It will be removed. Then, just drag a combobox on that column. It will appear in the grid, in the property sheet and you'll be able to proceed from there.