95 Ford Explorer will not shift into reverse or neutral. all other gears work.

What is your question?

The SUV has 260,xxx miles, runs fair for it's age and lack of upkeep prior to buying it. O/D light flashes at startup, and the SUV will not shift into Neutral or Reverse. Drive and all other gears work fairly well, there is some grinding if the weather is cold or accelerating too quickly. Some please help, it's the only vehicle I own with heat/air, and I have three kids, lol.