delay() or timeout with stop()?

You need to use setTimeout() in this case because of how .delay() works (and your inability to cancel it).

$('.file a').live('mouseenter', function() {  $.data(this, 'timer', setTimeout(function() {      $('#download').stop(true, true).fadeIn('fast');  }, 1000));}).live('mouseleave', function() {  clearTimeout($.data(this, 'timer'));  $('#download').stop(true, true).fadeOut('fast');});

You can give it a try here.

If you use .delay() it'll dequeue the next animation for the element, regardless of if you cleared that queue earlier. So you need a timeout that you can cancel, which the above does by manually calling setTimeout() and storing the result with $.data() so you can clear it later, via clearTimeout().

I was looking for the answer to a similar question, and I found that .animate() could also be used to handle this, and it obeys .stop()

It would look something like this:

$('.file a').live('mouseenter', function() {    $('#download')        .stop(true, true)        .animate({opacity:0}, 1000);            // one second delay        .animate({opacity:1}, 'fast', 'swing');}).live('mouseleave', function() {    $('#download')        .stop(true, true)        .animate({opacity:0}, 'slow', 'swing');});

Use a setTimeout function

$('.file a').live('mouseenter', function() {setTimeout(function(){    $('#download').stop(true, true).fadeIn('fast');}, 1000);}).live('mouseleave', function() {    $('#download').stop(true, true).fadeOut('fast');});

setTimeout will execute the code inside the function after the specified miliseconds (in this case 1000).