links and layers

I am new to Javascript/DHTML and I have a layer problem which I don't know how to solve.
I've created an image map in the form of a hand held device (see text representation below).

/--------------------------------------
| /------------------ |
| o Search | | |
| | | |
| o Gaming | screen | |
| | | |
| o Homepages | | |
| | | |
| o Emails | | |
| ------------------/ |
--------------------------------------/

The bullets are links. I've created named layers for all the links which correctly aligned in the screen area. The effect I want is when the bullet for the category is clicked, text and links are displayed in the screen area. Of course when another bullet is clicked, the previous screen display (layer) is made invisible and the new layer made visible. I use Netscape browser.

Below is part of the code form the image map/layer

------------------------------------------------------------------------
<center>
<span style="position: relative">
<img ISMAP SRC="navigatorpad.jpg" BORDER=0 USEMAP="#TJ Navigator" >
<map NAME="TJ Navigator">

<span style="position: relative">
<area SHAPE=RECT COORDS="66,65,82,78" HREF="search.htm">
<area SHAPE=RECT COORDS="66,87,82,101" HREF="gaming.htm">
<area SHAPE=RECT COORDS="66,108,83,123" HREF="homepages.htm">
<area SHAPE=RECT COORDS="67,131,82,144" HREF="emails.htm">
<area SHAPE=RECT COORDS="67,153,82,166" HREF="yelpages.htm">
<area SHAPE=RECT COORDS="68,176,82,188" HREF="compustores.htm">
<area SHAPE=RECT COORDS="68,197,82,209" HREF="auctions.htm">
<area SHAPE=RECT COORDS="68,219,81,232" HREF="plasticlinks.htm">
<area SHAPE=RECT COORDS="67,242,82,254" HREF="others.htm">
</map>
</span>
</center>
<span style="position:absolute; top: 50px; left: 220px">Welcome to TJ Navigator
Click button at left&nbsp;</span></span>
<layer NAME="choice0" LEFT=220 TOP=50 width=400 VISIBILITY="HIDE">
Search Engines
<br>Infoseek
<br>Alltheweb
<br>Dogpile
<br>Northernlight
<br>Raging
<br>Altavista
<br>
</layer>
.
.
.
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I would be most grateful if any of you could email me the solution at
ttj57@hotmail.com

Thanks a million.