You'll need to loop through all the items and test the Tag of each one. When you find one that has the value 2 you select that item and exit the loop:
vb.net Code:
For Each item As ListViewItem In myListView.Items
If CInt(item.Tag) = 2 Then
item.Selected = True
Exit For
End If
Next
If you would want to deselect any other items that might already be selected then you can do this:
vb.net Code:
For Each item As ListViewItem In myListView.Items
item.Selected = (CInt(item.Tag) = 2)
Next
Note that both these code snippets rely on the fact that all items have an Integer assigned to their Tag property.