I have a BIG table to output to HTML and into the browser. When the table is 200 lines, it's fine, but when it 20,000 lines, it chokes the browser. I output everything into a variable with
$html .= '<td> and <th>'
Anyway, to make it, you have to load ALL THE ROWS, and show only 20, which causes the same choking!
That's definitely a bad idea. I would write a method in your model that gets the next n number of records. You can call this method via Ajax on initial page load, and then again each time the user clicks a "Next N Entries" link and update the page.
You definitely don't want to load the HTML for 20K items and use jQuery to hide and show n records at a time; the DOM traversal will take FOREVER in the good browsers and will completely crash IE.