1993 Nissan Maxima

My son bought a 1993 Nissan Maxima. It drove fine, just needed a new battery. Then about 20-30 minutes into the drive home, if he had to slow down, the car would not speed back up. The RPM's were high and he said it would jerk before finally speeding up. I am betting it is transmission, which will cost more than the car is worth. But am also wondering if it could be the fuel pump. Any suggestions? I am car illiterate, so I have no idea what type of engine etc it has!

As of tonight it will not move at all. We could not even get it to move in neutral.