When you enter code into the product description area, you have to be very careful that the code is written correctly. There are a number of errors/omissions in the code posted above (calling out the table as 0 width, not specifying cellpadding or cellspacing, use of <font> tags, no breaks between lines, etc, no align settings). Certain browsers like IE are tolerant of code mistakes, others (like Firefox) are much more picky
Try cleaning up the code and see if that helps.