ヘッダ部分
<SCRIPT LANGUAGE="JavaScript">
function inspect(form) {
alert(form.select_test.options)
}
</SCRIPT>
ボディ部分
<FORM>
<SELECT NAME="select_test" SIZE=1>
<OPTION VALUE="1">No.1
<OPTION SELECTED VALUE="2">No.2
<OPTION VALUE="3">No.3
</SELECT>
<INPUT TYPE="button" NAME="check" VALUE="調べる" onClick="inspect(this.form)">
</FORM>