You can track email open rates, banner impressions and popup impressions by using the invisible 1x1 gif image trick.
For example, say you want to track email open rates, create a campaign called "openrate" and make the destination url: http://yourdomain.com/adtrackzgold/openrate.gif
So if a visitor clicks on your "openrate" campaign, they'll be taken to a 1x1 invisible gif image. However, nobody will click on this campaign, as you'll see.
Put this code near the top of the email, after the body tag.
When somebody opens their email, the html will call your tracking link to display the 1x1 gif image. The image is invisible, so the visitor doesn't see it, and a click has been registered so you know that the visitor opened the email.
You can also use the same principle to track pop up ads and banner impressions.