You can add a bit of customization easily with Content Editor Web Part, where you add Javascript and HTML. In this post you can find a snippet for SharePoint 2010 to open a custom page in the modal dialog window.

The solution consists of two parts - javascript function nad HTML code to call it.

Javascript function:

    function showFeedbackPage() {
        var pageUrl = 'http://path_to_your_page';
        var options = SP.UI.$create_DialogOptions();
        options.url = pageUrl;
        options.showClose = true;
        options.allowMaximize = true;
        SP.UI.ModalDialog.showModalDialog(options);
    }

 

HTML code to call the function:

<span class="module-link" onclick="showFeedbackPage()">Open in modal dialog window</span>