To do so you need to override MonoX DiscussionBoard and DiscussionTopics modules and add them to DiscussionContainer module.
1. DiscussionBoard Markup:
<%@ Control Language="C#"
AutoEventWireup="True"
CodeBehind="DiscussionBoard.ascx.cs"
Inherits="YourNamespace.DiscussionBoard"
%>
<%@ Register Namespace="MonoSoftware.Web.Pager" Assembly="MonoSoftware.Web.Pager"
TagPrefix="mono" %>
<%@ Register TagPrefix="MonoX" TagName="StyledButton" Src="/MonoX/controls/StyledButton.ascx" %>
<%@ Register Src="/MonoX/controls/CustomRadEditor.ascx" TagPrefix="mono" TagName="CustomRadEditor" %>
<%@ Register TagPrefix="MonoX" TagName="UserEntry" Src="/MonoX/controls/UserPicker.ascx" %>
<asp:UpdatePanel ID="upNewBoard" runat="server" UpdateMode="Conditional" ChildrenAsTriggers="true">
<ContentTemplate>
<div style="overflow: hidden;">
<asp:HyperLink ID="lnkLastActiveTopics" runat="server" CssClass="discussion-link" ></asp:HyperLink>
<asp:HyperLink ID="lnkMyTopics" runat="server" CssClass="discussion-link" ></asp:HyperLink>
<asp:UpdateProgress ID="upTop" runat="server" DisplayAfter="0" DynamicLayout="true">
<ProgressTemplate>
<img src='<%= BaseSiteFullUrl %>/App_Themes/<%= Page.Theme %>/img/loading.gif' alt="Progress ..."
width="20px" class="progress" />
</ProgressTemplate>
</asp:UpdateProgress>
<MonoX:StyledButton ID="btnNewBoard" runat="server" CssClass="discussion-button" />
</div>
<div class="discussion board-container">
<asp:PlaceHolder ID="plhNewBoard" runat="server" Visible="false">
<div class="input-form discussion-form">
<dl>
<dd>
<asp:ValidationSummary ID="summary" runat="server" DisplayMode="List" ShowSummary="true" />
</dd>
<dd>
<asp:Label ID="lblBoardName" runat="server" AssociatedControlID="txtBoardName"></asp:Label>
<asp:TextBox ID="txtBoardName" runat="server"></asp:TextBox>
<asp:RequiredFieldValidator ID="vldRequiredBoardName" runat="server" ControlToValidate="txtBoardName" Text="!" CssClass="validator ValidatorAdapter" Display="Dynamic" />
</dd>
<dd>
<asp:Label ID="lblBoardDescription" runat="server" AssociatedControlID="txtBoardDescription"></asp:Label>
<asp:TextBox ID="txtBoardDescription" runat="server" TextMode="MultiLine" Rows="10"></asp:TextBox>
<div>
<mono:CustomRadEditor Width="100%" ID="radBoardDescription" EditModes="Design"
runat="server" ToolBarMode="ShowOnFocus" StripFormattingOptions="AllExceptNewLines" ></mono:CustomRadEditor>
</div>
</dd>
<dd>
<asp:Label ID="lblEditors" runat="server" AssociatedControlID="ddlEditors"></asp:Label>
<div>
<MonoX:UserEntry runat="server" Height="200" Width="98%" ID="ddlEditors" UserFilterMode="ShowAllUsers" ExcludeMySelf="false" />
</div>
</dd>
<dd id="rowAutoSubscribe" runat="server">
<asp:CheckBox ID="chkSubscribe" runat="server" Checked="true" />
<asp:Label ID="labSubscribe" runat="server" AssociatedControlID="chkSubscribe"></asp:Label>
</dd>
<dd id="rowRoles" runat="server">
<asp:Label ID="labRoles" runat="server" AssociatedControlID="chkRoles"></asp:Label>
<asp:CheckBoxList ID="chkRoles" runat="server" CellSpacing="10"
RepeatColumns="5" RepeatDirection="Horizontal" RepeatLayout="Table">
</asp:CheckBoxList>
</dd>
<dd>
<MonoX:StyledButton ID="btnSaveNewBoard" runat="server" CommandName="Save" CssClass="discussion-styled-button" />
<MonoX:StyledButton ID="btnCancelNewBoard" runat="server" CausesValidation="false" CssClass="discussion-styled-button" />
</dd>
</dl>
</div>
</asp:PlaceHolder>
<asp:ListView ID="lvDB" runat="server">
<LayoutTemplate>
<asp:PlaceHolder ID="itemPlaceholder" runat="server"></asp:PlaceHolder>
</LayoutTemplate>
<ItemTemplate>
</ItemTemplate>
</asp:ListView>
</div>
<div style="clear: both">
<mono:Pager runat="server" ID="pager" PageSize="10" NumericButtonCount="5" AllowCustomPaging="true"
AutoPaging="false">
<PagerTemplate>
</PagerTemplate>
</mono:Pager>
</div>
</ContentTemplate>
</asp:UpdatePanel>
2. Code Behind:
You need to repeat this two steps for DiscussionTopics module and set the btnNewTopic text in code behind.
Please note that you need to replace "YourNamespace" with the one you use. When you finish those two user controls you need to add them to Discussion container.