Overriding Joomla Template Styles & Fixing Table Row Height

See more:

CSS

HTML

On this page:

http://www.irricad.com/software-database[^]

when the user checks the 'accept' box, the download links are 'unhidden', but this causes the table rows to change size, which looks awful. I've spent hours trying to stop it but I can't figure it out. How can I fix the table row height to an absolute size irrespective of the content? (So far, despite the download image only being 18px high, I have to set the row height to something like 60px to stop it changing size, and that looks even worse).

Or should/can I do away with the table and tabulate everything anouther way (CSS?)

Cheers.