var html = @"
    <table border=""0"" cellpadding=""0"" cellspacing=""0"" id=""table2"">
        <tr>
            <th>Name
            </th>
            <th>Age
            </th>
        </tr>
            <tr>
            <td>Mario
            </td>
            <td>Age: 78
            </td>
        </tr>
                <tr>
            <td>Jane
            </td>
            <td>Age: 67
            </td>
        </tr>
                <tr>
            <td>James
            </td>
            <td>Age: 92
            </td>
        </tr>
    </table>";

var doc = new HtmlAgilityPack.HtmlDocument();

doc.LoadHtml(html);

foreach (var cell in doc.DocumentNode.SelectNodes("//table[@id='table2']/tr/td"))
{
    Console.WriteLine(cell.InnerText);
}