怎么样实现这样的效果???

<script language="javascript">//Math.random() var scrollerheight=240; // 胶农费矾狼 技肺 
var html,total_area=0,wait_flag=true;

var bMouseOver = 1;
var scrollspeed = 1; // Scrolling 加档         
var waitingtime = 3000; // 肛眠绰 矫埃
var s_tmp = 0, s_amount = 60;
var scroll_content=new Array();
var startPanel=0, n_panel=0, i=0;

function startscroll()
{ // 胶农费 矫累
i=0;
for (i in scroll_content)
n_panel++;

n_panel = n_panel -1 ;
startPanel = Math.round(Math.random()*n_panel);
if(startPanel == 0)
{
i=0;
for (i in scroll_content) 
insert_area(total_area, total_area++); // area 火涝
}
else if(startPanel == n_panel)
{
insert_area(startPanel, total_area);
total_area++;
for (i=0; i<startPanel; i++) 
{
insert_area(i, total_area); // area 火涝
total_area++;
}
}
else if((startPanel > 0) || (startPanel < n_panel))
{
insert_area(startPanel, total_area);
total_area++;
for (i=startPanel+1; i<=n_panel; i++) 
{
insert_area(i, total_area); // area 火涝
total_area++;
}
for (i=0; i<startPanel; i++) 
{
insert_area(i, total_area); // area 火涝
total_area++;
}
}
window.setTimeout("scrolling()",waitingtime);
}
function scrolling(){ // 角力肺 胶农费 窍绰 何盒
if (bMouseOver && wait_flag)
{
for (i=0;i<total_area;i++){
tmp = document.getElementById('scroll_area'+i).style;
tmp.top = parseInt(tmp.top)-scrollspeed;
if (parseInt(tmp.top) <= -scrollerheight){
tmp.top = scrollerheight*(total_area-1);
}
if (s_tmp++ > (s_amount-1)*scroll_content.length){
wait_flag=false;
window.setTimeout("wait_flag=true;s_tmp=0;",waitingtime);
}
}
}
window.setTimeout("scrolling()",1);
}
function insert_area(idx, n){ // area 火涝
html='<div style="left: 0px; width: 100%; position: absolute; top: '+(scrollerheight*n)+'px" id="scroll_area'+n+'">\n';
html+=scroll_content[idx]+'\n';
html+='</div>\n';
document.write(html);
} // 胶农费矾俊 甸绢哎 郴侩甸阑 怕弊客 窃膊 持绢 凛聪促 
//scroll_content[0]="<iframe src='/main_inc/news/kbs_news.html' width='340' height='126' scrolling=no frameborder=0 leftmargin=0 topmargin=0 marginheight=0 marginwidth=0></iframe>";
//scroll_content[1]="<iframe src='main_inc/news/sports_news.html' width='340' height='126' scrolling=no frameborder=0 leftmargin=0 topmargin=0 marginheight=0 marginwidth=0></iframe>";
scroll_content[0]="<table width=100% height=60 cellspacing=0 cellpadding=3><tr><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=10860&ext_mall=myfolder target=_parent><img src=http://shopping.myfolder.net/img_prd/10860_115.jpg width=50 height=50 border=0></a></td><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=10860&ext_mall=myfolder target=_parent>MP3,VCD甫 犁积矫虐哥 府葛能档 ...</a><br><font color=#087E00><b>49,500盔</b></font></td></tr><tr><td colspan=2 background=http://image.myfolder.net/0317/Image/dot_line.gif></td></tr></table><table width=100% height=60 cellspacing=0 cellpadding=3><tr><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=11598&ext_mall=myfolder target=_parent><img src=http://shopping.myfolder.net/img_prd/11598_115.jpg width=50 height=50 border=0></a></td><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=11598&ext_mall=myfolder target=_parent>寇厘窍靛+DIVX敲饭捞鳖瘤 啊瓷茄...</a><br><font color=#087E00><b>187,000盔</b></font></td></tr><tr><td colspan=2 background=http://image.myfolder.net/0317/Image/dot_line.gif></td></tr></table><table width=100% height=60 cellspacing=0 cellpadding=3><tr><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=5493&ext_mall=myfolder target=_parent><img src=http://shopping.myfolder.net/img_prd/5493_115.jpg width=50 height=50 border=0></a></td><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=5493&ext_mall=myfolder target=_parent>公急栏肺 牢磐齿,颇老傍蜡 2俺 1...</a><br><font color=#087E00><b>74,000盔</b></font></td></tr><tr><td colspan=2 background=http://image.myfolder.net/0317/Image/dot_line.gif></td></tr></table><table width=100% height=60 cellspacing=0 cellpadding=3><tr><td><a href=http://shopping.myfolder.net/gonggu/gonggu_detail.asp?g_id=763&ext_mall=myfolder target=_parent><img src=http://shopping.myfolder.net/img_gonggu/763_115.jpg width=50 height=50 border=0></a></td><td><a href=http://shopping.myfolder.net/gonggu/gonggu_detail.asp?g_id=763&ext_mall=myfolder target=_parent>USB牡+勤靛迄面傈扁+傍扁没沥扁</a><br><font color=#087E00><b>39,800盔</b></font></td></tr><tr><td colspan=2 background=http://image.myfolder.net/0317/Image/dot_line.gif></td></tr></table>";
scroll_content[1]="<table width=100% height=60 cellspacing=0 cellpadding=3><tr><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=11642&ext_mall=myfolder target=_parent><img src=http://shopping.myfolder.net/img_prd/11642_115.jpg width=50 height=50 border=0></a></td><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=11642&ext_mall=myfolder target=_parent>棵覆仟胶 叼墨,漂啊 魄概</a><br><font color=#087E00><b>459,000盔</b></font></td></tr><tr><td colspan=2 background=http://image.myfolder.net/0317/Image/dot_line.gif></td></tr></table><table width=100% height=60 cellspacing=0 cellpadding=3><tr><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=10791&ext_mall=myfolder target=_parent><img src=http://shopping.myfolder.net/img_prd/10791_115.jpg width=50 height=50 border=0></a></td><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=10791&ext_mall=myfolder target=_parent>匙飘况农 叼胶农 傍蜡啊瓷+寇厘窍...</a><br><font color=#087E00><b>179,000盔</b></font></td></tr><tr><td colspan=2 background=http://image.myfolder.net/0317/Image/dot_line.gif></td></tr></table><table width=100% height=60 cellspacing=0 cellpadding=3><tr><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=11607&ext_mall=myfolder target=_parent><img src=http://shopping.myfolder.net/img_prd/11607_115.jpg width=50 height=50 border=0></a></td><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=11607&ext_mall=myfolder target=_parent>MP3档 登绊 USB历厘厘摹档 登绊 ...</a><br><font color=#087E00><b>59,000盔</b></font></td></tr><tr><td colspan=2 background=http://image.myfolder.net/0317/Image/dot_line.gif></td></tr></table><table width=100% height=60 cellspacing=0 cellpadding=3><tr><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=11544&ext_mall=myfolder target=_parent><img src=http://shopping.myfolder.net/img_prd/11544_115.jpg width=50 height=50 border=0></a></td><td><a href=http://shopping.myfolder.net/product_info.asp?p_id=11544&ext_mall=myfolder target=_parent>PDA客 GPS 矫胶袍捞 窃膊 Mio168...</a><br><font color=#087E00><b>690,000盔</b></font></td></tr><tr><td colspan=2 background=http://image.myfolder.net/0317/Image/dot_line.gif></td></tr></table>";
</script>
<span style="width: 100%; position: relative; height: 240px" id="main2">
<div style="left: 0px; width: 100%; clip: rect(0px 100% 240px 0px); position: absolute; top: 0px; height: 15px" onMouseover="bMouseOver=0" onMouseout="bMouseOver=1" id="scroll_image">
<script>
startscroll(); //2绰 panel狼 肮荐
</script>
</div>
</span>