A tall cabinet (24" deep if you can get it) with pull-out trays will give you more storage space than a "walk-in" pantry (picture 1). Most walk-ins give you room to stand in, but very little storage. Picture #1 will hold more goods than Picture #2 (with door - the door blocks you accessibility) and Picture #3 (these look impressive, but actually hold very little because the shelves are so shallow and not adjustable - best you can store is one small soup can on the swinging shelves, and the back shelves (inside) are only 12" deep and no lighting!).

The first pantry also allows you to fully-extend the shelves (with proper hardware) so you can stand to the side of the pull-out and still reach items on the back the of the tray very easily. Hope this helps.