technopeasant, it sounds like you are using a jquery plugin (in your example, a plugin called 'fillit') and it is asking you to run the plugin on a tag or series of tags. Sorry if I misunderstood your question.
If that is the case, all you need to do is one of two things. If you are trying to run it on a very specific element in the HTML page (one with an id like <div id="myvideo"></div>) then all you need to do is run:
$('#myvideo').fillit();
//Notice the '#' symbol, that looks up the element with an id of 'myvideo'
If you want to run the plugin on a series of elements (like all <p> tags in the entire document, you'd run something like:
$('p').fillit()
//notice no '#', it's just looking up all <p> tags regardless of ID.
Take a look at the jQuery documentation regarding selectors to get a more concrete idea of how these selectors work:
http://docs.jquery.com/How_jQuery_Works
$('video').fillit()?fillit()function that you can use like$(".mySelector").fillit();? If so, you can follow the steps here to do it.