How to fix height of TR?

Tables are iffy (at least, in IE) when it comes to fixing heights and not wrapping text. I think you’ll find that the only solution is to put the text inside a div element, like so:

td.container > div {
    width: 100%;
    height: 100%;
    overflow:hidden;
}
td.container {
    height: 20px;
}

<table>
    <tr>
        <td class="container">
            <div>This is a long line of text designed not to wrap 
                 when the container becomes too small.</div>
        </td>
    </tr>
</table>

This way, the div‘s height is that of the containing cell and the text cannot grow the div, keeping the cell/row the same height no matter what the window size is.