You will need a copy of Paint Shop Pro. I'm using vX but you should be able to adapt this to any release of PSP.
You will also need a door tube. If you don't have one, you can download mine HERE.
I saved it in PSD format so you should have no problem opening it.
Once you open it, you can tube it. Start with an new image:
Place your tube in the center.
Select the selection tool with the following settings:
and draw it around the door (try to stay off the molding.)
Select Edit>Cut>Edit>Paste As New Layer. Deselect. Center the new door layer into the molding.
With the door layer selected, choose the Deform tool
Whle holding down the Control key, select the top right node and begin to pull up until you have the angle that you want. You're not pulling the whole door top up. When you hold your cursor over the top-right node, your symbol is . When you press the Control key your cursor changes to Notice that pulling up on the top node also moves the bottom right node down for the proper perspective.
While you still have the Deform tool selected, place your cursor on the center node on the right and begin to push to the left until you have the door opened as far as you'd like.
Now create a new layer and set your Materials palette to:
With the Rectangle tool:
draw out a rectangle to make the edge of the door.
Now you have to adjust the angle of the door's edge to match the perspective. Again select the Deform tool:
Hold down the Control key and pull the top node on the right down a little until you are happy with the angle. Use the same technique as you did on the door, except you are pushing down now and not pulling up.
Now you're done and you should have this: