Why are you using a form for this? Why don't you just use plain images and hyperlinks?
Code:
<a href="wherever.php"><img src='back.png'></a><br>
<a href="wherever.php"><img src='save.png'></a><br>
<a href="wherever.php" id="forward_button"><img src='forward.png'></a>
<script language=javascript>
document.onkeydown=function(){catchKey;}
function catchKey()
{
if(event.keyCode==13)document.getElementById('forward_button').click();
}
</script>
HTH,
Snib
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