Using windows live write you can also open your old blog posts edit and update them. You can delete them also.
For this you have to click on open Recent Post menu.
It is confusing in sense that when you move your mouse to this menu it will open sub menu with recent post list. But if you click on Open Recent Post menu button then it will open blog post open dialog.
In above dialog in left side you can see Draft, Recently Posted, and all configured blog list.
When you will select items in left list then in right list it will display all post list.
From here you can select blog post for editing and you can delete using delete button. Fro show drop down list item you can select no of post to display and from filter text box you can filter your post by title.