Most form controls in modern browsers tend to have a Windows XP or better look and feel to them. Thus buttons will appear with curved corners - though in Opera this is an option that has to be turned on:Tools Menu -> Appearance ->Skins Tab -> Windows Native.
Combo boxes created via the
<select>
<style class="...">
. The degree of responsiveness is browser dependant with the worst culprit being IE6 - can’t speak with authority of IE5.5 etc, it has been a long time since I used it.
Here is a way round the problem
http://www.explainth.at/en/html/selstyle.shtml
The technique relies on making the <select> completely transparent. Unfortunately, this means it will not work in IE6 since IE6 selects seem to ignore the opacity setting.