URL: this is the thing that begins with http:// that people type in to get to your page
Keywords to search for: these are what the script will search for when looking for your page.
Time:
While the actual time it takes per search engine varies greatly, you can probably expect each search engine to add about 5 seconds. While this is considerably faster than doing it by hand, it does tend to add up. In short, if you leave all 15 search engines checked, you can expect it to take about 75 seconds or so.