The hungarian strategy was not so bad. They were outnumbered, and the hungarian genaral (Tomori Pál) planed a defensive fight. But he saw a chance when the turks arrived, and tried a risky attack, because he knew, the whole ottoman army is not on the battlefield yet. This is the reason, why this charge looked so unorganized.
After the first success of the light cavalry of the right flank, the cavalrymen did'nt really know, what they should do next.
And the heavycavalry, the hungarian center charged against the defense-line of the janissaries. That was a bit suicide, yes. The knights did it sometimes in the history.
And Suleyman also arrived with the rest of his forces.
The left flank fought the longest. Here stood many foot-soldiers, and they repeled some attacks of the ottoman light cavalry.
The hungarian king was called II. Lajos (not Janosh, Janos ruled after the death of II. Lajos), and he died after the battle. There was much rain, and he fell in a river, and weared a full armour.
The cristians: hungarians (heavy and light cavalry, infantry), czechs (infantry), polish (infantry), croatians (light cavalry) were about 25-28 000.
The ottomans: 60-70 000.