Danke für die schnellen Ratschläge aber leider funktioniert es son nocht nicht.
Ich poste mal meinen aktuellen Code bei dem die Seite immer an den Anfang springt:
<TABLE BORDER=0 CELLPADDING=0 CELLSPACING=10>
<TR>
<td rowspan="4" width="435">
<div align="center">
<img src="http://www.curlingclubhamburg.com/ebay/NV-M7_01.jpg" name="screen"> </div>
</td>
<td><a href="#" onMouseUp="document.images['screen'].src = 'http://www.curlingclubhamburg.com/ebay/NV-M7_01.jpg'; return false;"><img src="http://www.curlingclubhamburg.com/ebay/NV-M7_01_s.jpg" border="0"></a></td>
</TR>
<tr height="20">
<td height="20"><a href="#" onMouseUp='javascript:document.images["screen"].src = "http://www.curlingclubhamburg.com/ebay/NV-M7_02.jpg";' onFocus="blur()"><img src="http://www.curlingclubhamburg.com/ebay/NV-M7_02_s.jpg" border="0"></a></td>
</tr>
<tr>
<td><a href="#" onMouseUp='javascript:document.images["screen"].src = "http://www.curlingclubhamburg.com/ebay/NV-M7_03.jpg";' onFocus="blur()"><img src="http://www.curlingclubhamburg.com/ebay/NV-M7_03_s.jpg" border="0"></a></td>
</tr>
<tr>
<td><a href="#" onMouseUp='javascript:document.images["screen"].src = "http://www.curlingclubhamburg.com/ebay/NV-M7_04.jpg";' onFocus="blur()"><img src="http://www.curlingclubhamburg.com/ebay/NV-M7_04_s.jpg" border="0"></a></td>
</tr>
</TABLE>