narrow xdocument in c#

Is there any way to to cut off some part of xDocument and still getting xDocument? By cutting off I mean keeping selected node.
I have XML like this:

<something 1>
    <object>
        Name="The only object I need"
        <lev1>
            <lev2>
                Name= "Attribute I need"
            </lev2>
            <lev2>
                Name= "Attribute I also need"
            </lev2>
        </lev1>
    </object>
    <object>
        Name="Thing I want to remove"
        <lev1>
            <lev2>
                Name= "useless attribute"
            </lev2>
            <lev2>
                Name= "second useless atribute"
            </lev2>
        </lev1>
    </object>
</something 1>

I need xDocument object containing only object with Name= "Attribute I need". I know it's easy, but I can't find it.
Edit:
I'm talking about a lot of really immense XML files. Therefore I can't just select something to remove.

Jon Skeet
people
quotationmark

You mean you want only the first child node? Yes, that's simple using the Remove extension method:

doc.Root.Elements().Skip(1).Remove();

Sample:

using System;
using System.Linq;
using System.Xml.Linq;

class Test
{
    static void Main()
    {
        var doc = new XDocument(new XElement ("root",
            new XElement("child1", new XElement("grandchild1")),
            new XElement("child2", new XElement("grandchild2"))));

        Console.WriteLine("Document before:");
        Console.WriteLine(doc);

        doc.Root.Elements().Skip(1).Remove();

        Console.WriteLine("Document after:");
        Console.WriteLine(doc);
    }
}

Output:

Document before:
<root>
  <child1>
    <grandchild1 />
  </child1>
  <child2>
    <grandchild2 />
  </child2>
</root>
Document after:
<root>
  <child1>
    <grandchild1 />
  </child1>
</root>

To generalize this, you'd just want to change the Skip call to select the elements you don't want to keep:

doc.Root
   .Elements()
   .Where(x => (string) x.Attribute("name") != "name to keep")
   .Remove();

people

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