Попробуй
button type="submit", стиль лучше тогда поменять
<form action="http://80.68.5.27/cgiopac/opacg/opac.exe" method="post" target="_blank"><input type="hidden" name="arg0" value="11111" size="5" /> <input type="hidden" name="arg1" value="111111" size="6" /> <input type="hidden" name="TypeAccess" value="PayAccess" />
<h8 style="cursor: pointer;"><button type="submit" style="color: #4169E1; font-size: 18pt; font-family: Georgia, serif;">Электронный каталог ЦБС г.Таганрога</button></h8>
</form>
<form action="http://80.68.5.27/cgiopac/opacg/opac.exe" method="post" target="_blank"><input type="hidden" name="arg0" value="11111112222" size="5" /> <input type="hidden" name="arg1" value="1111111122222" size="6" /> <input type="hidden" name="TypeAccess" value="PayAccess" />
<h8 style="cursor: pointer;"><button type="submit" style="color: #4169E1; font-size: 18pt; font-family: Georgia, serif;">Электронный каталог ЦБС г.Таганрога 111</button></h8>
</form>
