Space and a line into the catagory list

Please can someone help. I have really tried to find answers to these problems without starting a new thread, but I don't even know what I should be typing into the search box for for some of this.
I would like to take the spaces out of the header and put space and a line into the catagory list.
I thought a picture would be the best way to show you what I mean. I hope it works...

If you need the address for the site, it is - http://www[dot]moonmoose.com/moody/

For the listing:
In your stylesheet (/includes/templates/your_template/css/stylesheet.css), add

/* space & border between listing items */
.productListing-odd td, .productListing-even td {
text-align: left;
vertical-align: top;
padding:0.5em;
margin-bottom: 1em;
border-bottom: 3px double #aaccbb;
}

Change numbers, add, edit or delete properties as desired.

For the header, I will have to look at your site directly. Hang on a while.

Depending on your browser, those spaces in the header may be caused by the <br class="clearBoth" /> lines. You could try changing them to just <br /> or instead of class="clearBoth" try an inline style change of line-height: 0px

Wow!
The space and line mod is perfect, and it took me no time at all.
I've been just looking at it for ages, clicking in and out of the list page.
(I know I get excited far to easily, but there you have it)
It's so much better than it was. Thanks gjh42, you're a star!

I went into the picture measurements list in my admin section and changed the size of the pictures in the list so that they are always the same width with no measurement for the height, that made it better still. :D

I'm off to try out the header suggestions now.

And thank-you Chinchilla.

I returned to the header tpl.header.php file and searched out the lines of code you pointed to and I have arrived at a layout that I'm really pleased with.

Thanks again to both of you. :D