You are correct, support for width and height attributes within tables, TDs, and TRs vary from one browser to the next.
In fact we have come to avoid the height attribute entirely because it is unpredictable. Instead, I recommend using the old method of creating a transparent GIF in order to force the width or height of each TD. For example:
<img src="clear.gif" width="300" height="1">
<img src="clear.gif" width="100" height="1">
When using this method, just BE AWARE: Outlook 07 and 2010 ignore the width and height attributes within the image element, so you can’t just stretch the clear GIF to whatever width/height you want, you actually need to use a clear GIF with exact dimensions for each instance.
I sincerely hope this helps!