You can't use padding-left like this, you either need "padding-left" or paddingLeft for the property name, like this:
$('#mytable tr').toggle(function(){
$(this).animate({'padding-left': '+=50px'}, 2000);
}, function(){
$(this).animate({'padding-left': '-=50px'}, 2000);
});
Or this:
$('#mytable tr').toggle(function(){
$(this).animate({paddingLeft: '+=50px'}, 2000);
}, function(){
$(this).animate({paddingLeft: '-=50px'}, 2000);
});
In jQuery, anything property passed into .animate() or .css() with a capital in it gets replaced with -lower, so paddingLeft gets converted to padding-left under the covers.
Edit: As Reigel points out in comments, you can't bind multiple functions to click, I think you meant .toggle() which is what I put above, this swaps between functions on each click event.