Hai,
Its working.The thing you have to do is change the XML Format like this

<ViewCategory>
<Menu Id="21" MenuName="Test1">
<Category Id="2" CategoryName="Book" />
<Category Id="3" CategoryName="Computer" />
</Menu>
<Menu Id="22" MenuName="Test2">
<Category Id="4" CategoryName="Book"1 />
<Category Id="5" CategoryName="Computer1" />
</Menu>
</ViewCategory>

If you have xml Format like this,then it will work.