It would be easier if you posted this bit of HTML to a public server so we could see it in action. (Once upon a time, some old crotchety ex-admin messed with the PHP so that the [code] tags used to HTML-escape < so that HTML could be posted easily, but vBulletin upgrades have reverted it back to default behavior... *cough*)

If you're using tables to try to align images as part of a site's layout, consider using CSS instead. This is what CSS is designed for. Table width (for example) is often not strictly observed by all browsers, but only taken as a suggestion. CSS also has the advantage that everything doesn't have to fit into same-sized rows and columns.