"La puerta está abierta."
Translation:The door is open.
Está is used with a location or temporary state. Es is used if it is an aspect of the thing.
You would say it the same in Spanish, but I think your sentence is improper English. In English, "open" is used as the adjective, while "opened" is only used in perfect constructions, à la "The door has been opened."
I was just about to comment that. That's the first thing that popped into my mind when I saw this. Lol
I CHIME IN WITH A "HAVEN'T YOU PEOPLE EVER HEARD OF, CLOSING A GOSHDARN DOOR, NO? IT'S MUCH BETTER TO FACE THESE KINDS OF THINGS, WITH A SENSE OF POISE AND RATIONALITY"
im sorry... i really am... yall have no idea how necessary that was.... I just sorta had a Panic! Attack.... Heh