Sounds like first gear is toast. I would guess the button you are pressing is the winter mode, that skips first gear (maybe second too, but I dunno, never used it). When you come to a stop, it tries to go back to first. I would just replace the tranny with a quality rebuilt model with a warranty. It could be as simple as a solenoid, but from what I have seen for the last few years, once they go, they are gone.