Smooth Show/Hide Effects? Is there a way?

<script>
var imgs=["http://www.opera.com/graphics/buttons/red_buy.gif","http://www.opera.com/graphics/buttons/red_dl.gif"]
function toggle(obj,nm)
{
     obj.src=obj.src==imgs[0]?imgs[1]:imgs[0];
     theDiv=document.getElementById(nm);
     theDiv.style.display=theDiv.style.display=="none"?"":"none";
}
</script>
Body:
<table border=0>
<tr>
     <td>
          <img src=http://www.opera.com/graphics/buttons/red_dl.gif onClick="toggle(this,'Arts')" border=0>
     </td>
</tr>
<tr>
     <td>
        <div id="Arts" style="position: relative; display:none;">
          Some content         Some content         Some content
         Some content          Some content         Some content         Some content
         Some content          Some content         Some content         Some content
         Some content          Some content         Some content         Some content
         Some content          Some content         Some content         Some content
         Some content          Some content         Some content         Some content
         Some content          Some content         Some content         Some content
         Some content          Some content         Some content         Some content
         Some content          Some content         Some content         Some content
         Some content
     </div>
     </td>
</tr>
</table>

very nice work!! but.. . it's not working right on my form.. it goes down smoothly but:

1. not fast enough
2. it makes my centered webpage turn to left indent
3. my form within the <div></div> is actually longer than what this script is set to go down... so it stops abruptly...

so if you could make this script relative to it's surroundings.. that would be fantastic.. and no grays please =)

looks like u spent a lot of time writing this script.. so i'll make another post requesting fixes...

Thanks for the feedback, as you may have probably noticed I have been away for a month. Is everything in order now or do you still require some assistance?