Can't open door...Help

I'd start by getting all the linkage moving like it should....outside handle and linkage, inside release lever and linkage, lock knob rod and linkage. If all that moves like it should, I probably would go through the door panel opening with the glass all the way up, and hit that latch with a propane/butane torch. Heat along with a swift kick from the inside, might pop that latch loose. Just be careful with where you kick. You don't want to bend the inside of the door shell.