RadioButtonList2.aspx font size:
View Sample
<head>
<title>Setting Layout in a RadioButtonList Control</title>
<link rel="stylesheet" href="/shared/netdemos.css">

<script language="C#" runat="server">
void Page_Load ( object src, EventArgs e ) {
   if ( !IsPostBack ) getSelected ( myList,null );
}

void getSelected ( object src, EventArgs e ) {
   if ( myList.SelectedIndex > -1 ) {
      msg.Text = "Destination " + myList.SelectedItem.Text;
      Image.ImageUrl = "~/shared/images/" + myList.SelectedItem.Value;
      Image.AlternateText = myList.SelectedItem.Text;
   }
}

void setDirection ( object src, EventArgs e ) {
   if ( chkDirection.Checked )
      myList.RepeatDirection = RepeatDirection.Horizontal;
   else
      myList.RepeatDirection = RepeatDirection.Vertical;
}
</script>
</head>

<body>
<!-- #include virtual="~/shared/top.inc -->
<div class="header"><h2>Setting Layout in a RadioButtonList Control</h2></div>

<!-- #include virtual="~/shared/viewsrc_top.inc" -->
<hr size=1 width=92%>

<form runat="server">

   <table cellpadding="10">
   <tr valign="top">
      <td>
         <asp:RadioButtonList id="myList" repeatcolumns=3 onSelectedIndexChanged="getSelected" autopostback runat="server">
            <asp:listitem selected value="earth.gif" text="Earth"/>
            <asp:listitem value="jupiter.gif" text="Jupiter"/>
            <asp:listitem value="mars.gif" text="Mars"/>
            <asp:listitem value="mercury.gif" text="Mercury"/>
            <asp:listitem value="neptune.gif" text="Neptune"/>
            <asp:listitem value="pluto.gif" text="Pluto"/>
            <asp:listitem value="saturn.gif" text="Saturn"/>
            <asp:listitem value="uranus.gif" text="Uranus"/>
            <asp:listitem value="venus.gif" text="Venus"/>
         </asp:RadioButtonList>

         <br>

         <asp:checkbox id="chkDirection" onCheckedChanged="setDirection" text="Display Horizontally" autopostback runat="server" />

      </td>
      <td align="center">
         <p><asp:Image id="Image" runat="server" />
         <p><asp:Label id="msg" runat="server" />
      </td></tr>
   </table>

</form>
<hr size=1 width=92%>
<!-- #include virtual="~/shared/viewsrc.inc" -->

</body>
</html>