I only have one blog on my site, so I felt there was no need to display the blog Groups list on the main blog page. It's simple enough to take out.

Open up the Themes/[theme]/Blogs/blogs.Master file, and comment out the CSBlog:GroupList control, as shown below:

<%--<CSBlog:GroupList runat="server">
    <QueryOverrides GroupID="-1" />
    <LeaderTemplate>
        <div class="CommonSidebarArea">
            <div class="CommonSidebarRoundTop"><div class="r1"></div><div class="r2"></div><div class="r3"></div><div class="r4"></div></div>
            <div class="CommonSidebarInnerArea">
                <CSControl:ResourceControl ResourceName="Groups" Tag="H4" CssClass="CommonSidebarHeader" runat="server" />
                <div class="CommonSidebarContent">
    </LeaderTemplate>
    <HeaderTemplate><ul class="CommonSidebarList"></HeaderTemplate>
    <ItemTemplate><CSBlog:GroupData LinkTo="GroupHome" Property="Name" runat="server" Tag="Li" /></ItemTemplate>
    <FooterTemplate></ul></FooterTemplate>
    <TrailerTemplate>
                </div>
                <CSControl:SiteUrl UrlName="webloghome" ResourceName="ViewAllGroups" Tag="Div" CssClass="CommonSidebarFooter" runat="server" />
            </div>
            <div class="CommonSidebarRoundBottom"><div class="r1"></div><div class="r2"></div><div class="r3"></div><div class="r4"></div></div>
        </div>
    </TrailerTemplate>
</CSBlog:GroupList>--%>

If you also want to remove the "Blogs on this Site" link, comment out the control about 8 lines above the previous section, as follows:

<%--<CSControl:SiteUrl ResourceName="Bloggers" UrlName="blog_aggregate_Bloggers_default" Tag="Li" runat="server" />--%>

That's it. I wish they were a setting in the admin, though.