Using the Enter key within a cell does not increase cell width but does
increase cell height, so I don't understand your question. You could try
using Shift-Enter, which inserts an end-of-line mark rather than a paragraph
mark. But neither of these affects text wrapping, which is automatic within
each cell and will increase cell height if it wraps to more than one line.
Try the following: Click Table Properties on the Table menu. Click the
Table tab. Click Options. If "Automatically resize to fit contents" is
checked, clear it, and click OK twice.